- A student writes the number 58.309. The digit 3 is in the tenths place and the digit 3 is also used in the hundredths place in the number 58.039. Which statement correctly compares the value of the digit 3 in these two numbers?
Answer: In 58.309, the 3 is worth 0.3, and in 58.039, the 3 is worth 0.03, so the first 3 is 10 times the second.
The value of a digit in a decimal number depends on its position or place relative to the decimal point. Each place to the left of another is 10 times greater in value than the place to its right. Conversely, each place to the right is 1/10 the value of the place to its left. For example, in 58.309, the 3 in the tenths place is worth 3 × 0.1 = 0.3, and in 58.039, the 3 in the hundredths place is worth 3 × 0.01 = 0.03, so the first 3 is exactly 10 times the second since the digits are the same. A common misconception is that the same digit always has the same value regardless of position, but place determines its true worth. Understanding place value allows us to compare digits across different numbers or positions by calculating their precise values. This knowledge helps us understand decimal relationships, making it easier to order, round, or perform calculations with decimals. - Compare these three numbers: In 285.67, the 5 represents A. In 28.567, the 5 represents B. In 2856.7, the 5 represents C. Which statement correctly describes the relationship between A, B, and C?
Answer: C=10A and A=10B, so C=100B
A = 5 (ones place), B = 0.5 (tenths place), C = 50 (tens place). Since C is in the tens place and A is in the ones place, C = 10A. Since A is in the ones place and B is in the tenths place, A = 10B. Therefore C = 100B. - A student writes the number 63.49 on a place value chart and underlines the digit 4: 63.<u>4</u>9. The digit 4 is in the tenths place and the digit 9 is in the hundredths place (adjacent places). Which statement about the value of the underlined digit is correct?
Answer: The underlined digit has a value of 0.4, which is 10 times the value of 0.04 in the hundredths place.
The value of a digit in a decimal number depends on its place relative to the decimal point. Each place value is 10 times the value of the place immediately to its right, meaning moving left multiplies the value by 10. Conversely, each place value is 1/10 of the value of the place immediately to its left, so moving right divides the value by 10. For example, in the number 63.49, the underlined digit 4 in the tenths place has a value of 0.4, which is 10 times the value a digit 4 would have in the hundredths place at 0.04. A common misconception is that moving right increases a digit's value, but actually, it makes the value smaller by a factor of 10. Understanding place value relationships allows us to accurately compare decimals, such as seeing that 0.4 is greater than 0.09. This knowledge also aids in interpreting numbers in charts, helping us grasp the significance of each digit's position.
- In the number 70,105.909, the digit 9 is in the tenths place and another 9 is in the thousandths place. Which statement correctly compares the two 9s?
Answer: The 9 in the tenths place is worth 0.9 and the 9 in the thousandths place is worth 0.009, so the tenths 9 is 100 times the thousandths 9.
The value of a digit in a decimal number depends on its position or place relative to the decimal point. Each place to the left of another is 10 times greater in value than the place to its right. Conversely, each place to the right is 1/10 the value of the place to its left. For example, in 70,105.909, the 9 in the tenths place is 9 × 0.1 = 0.9, and the 9 in the thousandths place is 9 × 0.001 = 0.009, so the tenths 9 is exactly 100 times the thousandths 9 since they are two places apart. A common misconception is that digits separated by multiple places have the same value if they are the same number, but each place multiplies the difference. Understanding place value helps us compare identical digits in non-adjacent positions by factoring the powers of 10. This awareness improves our ability to analyze and work with complex decimal numbers in various applications.
- A library has 70,070 books. In 70,070, the digit 7 in the ten-thousands place and the digit 7 in the tens place are the same digit but in different positions. Which statement correctly compares the value of the two digits 7?
Answer: The 7 in the ten-thousands place is 1,000 times the value of the 7 in the tens place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 70,070, the 7 in the ten-thousands place is worth 70,000, which is 1,000 times the 7 in the tens place at 70. A common misconception is that identical digits have the same value anywhere, but positions differ by powers of 10. Place value relationships allow comparisons across distant places by calculating factors of 10. This knowledge is essential for understanding number magnitude and operations.
- A classroom thermometer shows 23.45∘C. In the number 23.45, the digit 4 is in the tenths place and the digit 5 is in the hundredths place (these are adjacent places). Which statement about the value of the digit 4 is correct?
Answer: The digit 4 has a value of 0.4 because the tenths place is 10 times the hundredths place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 23.45, the digit 4 in the tenths place has a value of 0.4, which is 10 times the value of the digit 5 in the hundredths place at 0.05. A common misconception is that digits have fixed values regardless of position, but position multiplies the digit by the place's value, like tenths being 0.1. Understanding place value relationships allows us to compare digits across positions accurately. This knowledge helps in reading, writing, and operating on decimal numbers effectively.
- A decimal number contains the digit 8 in three different places: ones, hundredths, and ten-thousandths. If the 8 in the ones place has a value of 8, what is the sum of the values represented by all three 8s?
Answer: 8.0808 because you add 8+0.08+0.0008
When you see a question about place value, remember that each digit's value depends on its position in the number. The digit itself stays the same, but its actual value changes based on where it sits.
Let's work through this step by step. You have the digit 8 in three places: ones, hundredths, and ten-thousandths. To find each digit's value, you multiply the digit by its place value:
- The 8 in the ones place: 8×1=8
- The 8 in the hundredths place: 8×0.01=0.08
- The 8 in the ten-thousandths place: 8×0.0001=0.0008
Adding these values together: 8+0.08+0.0008=8.0808
Answer choice D correctly shows this calculation and gives the right sum.
Now let's see why the other answers miss the mark. Choice A gives 8.08008, which incorrectly places the ten-thousandths value in the hundred-thousandths place. Choice B suggests 8.888, falling into the trap of thinking each 8 has equal value regardless of position—this ignores how place value works. Choice C calculates 24 by simply multiplying 3×8, completely overlooking that place value determines actual worth, not just counting digits.
Study tip: When working with place value, always convert each digit to its actual value first, then add. Don't get fooled by how many times a digit appears—focus on where each digit sits in the number. - A science beaker has 4.08 liters of water. In 4.08, the digit 0 is in the tenths place and the digit 8 is in the hundredths place (adjacent places). Which statement about the digit 8 is correct?
Answer: The digit 8 has a value of 0.08 because it is in the hundredths place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 4.08, the digit 8 in the hundredths place has a value of 0.08, which is 1/10 of what it would be in the tenths place. A common misconception is that the value stays the same in any decimal place, but each place scales the digit by powers of 1/10. Knowing place value helps compare adjacent places and understand relative sizes. It also aids in performing calculations with decimals accurately.
- A class records a time as 3.408 minutes. The digit 4 is in the tenths place and the digit 0 is in the hundredths place (adjacent places). Which statement about the value of the digit 4 is correct?
Answer: The digit 4 has a value of 0.4, which is 10 times the value of 0.04 in the hundredths place.
The value of a digit in a decimal number depends on its place relative to the decimal point. Each place value is 10 times the value of the place immediately to its right, meaning moving left multiplies the value by 10. Conversely, each place value is 1/10 of the value of the place immediately to its left, so moving right divides the value by 10. For example, in the number 3.408, the digit 4 in the tenths place has a value of 0.4, which is 10 times the value a digit 4 would have in the hundredths place at 0.04. A common misconception is that you add place values together to find a digit's worth, but each digit's value is independent and position-based. Understanding place value relationships allows us to accurately compare timings or measurements, such as 0.4 minutes versus 0.08 minutes. This knowledge also enhances our ability to round or estimate decimals effectively in practical scenarios.
- Look at the number 62,718.043. The digit 4 is in the hundredths place and the digit 3 is in the thousandths place. Which statement about these two digits is correct?
Answer: The 4 is worth 0.04 and the 3 is worth 0.003, and the 4 is more than 10 times the value of the 3.
The value of a digit in a decimal number depends on its position or place relative to the decimal point. Each place to the left of another is 10 times greater in value than the place to its right. Conversely, each place to the right is 1/10 the value of the place to its left. For example, in 62,718.043, the 4 in the hundredths place is 4 × 0.01 = 0.04, and the 3 in the thousandths place is 3 × 0.001 = 0.003, so 0.04 is more than 10 times 0.003 (actually about 13.33 times) because 4 > 3. A common misconception is that place value relationships always yield exactly 10 times between adjacent places, regardless of digit values. Understanding place value enables us to compare digits' contributions across positions, even when they differ. This helps us comprehend the structure of decimals, improving skills in comparison and arithmetic.
- A number has a 7 in the tenths place with a value of 0.7. If you wanted to place another 7 in this number so that its value would be exactly 1001 of the original 7's value, where would you place it?
Answer: In the thousandths place, since 1001=101×101
The original 7 has value 0.7. We want (1/100) × 0.7 = 0.007. This means the new 7 should be in the thousandths place. Moving two places to the right decreases the value by 1/100, since each place represents 1/10 of the previous place. - A class collected 3,405 cans for a food drive. In 3,405, the digit 4 is in the hundreds place and the digit 0 is in the tens place (adjacent places). Which statement about the digit 4 is correct?
Answer: The digit 4 has a value of 400 because it is in the hundreds place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 3,405, the digit 4 in the hundreds place has a value of 400, which is 10 times the tens place value. A common misconception is that digits always represent their face value, but place multiplies them by powers of 10. Understanding place value helps compare whole number positions and their contributions. It enables us to read and interpret large numbers correctly.
- A student writes 3,450.806 and then moves the digit 8 from the tenths place to the hundredths place. How does the value of the digit 8 change when it moves one place to the right?
Answer: Its value becomes 101 as large.
The value of a digit in a decimal number depends on its position or place relative to the decimal point. Each place to the left of another is 10 times greater in value than the place to its right. Conversely, each place to the right is 1/10 the value of the place to its left. For example, moving the 8 from the tenths place (8 × 0.1 = 0.8) to the hundredths place in 3,450.806 makes it 8 × 0.01 = 0.08, which is 1/10 of its original value. A common misconception is that moving a digit right increases its value, but it actually decreases it by a factor of 10. Understanding place value helps us compare how digit positions affect the overall magnitude of a number. This insight is crucial for understanding decimal expansions and performing accurate calculations. - Ms. Chen writes a mystery decimal where one digit appears in both the tens place and the thousandths place. She says the digit in the tens place represents a value that is 10,000 times the value of the same digit in the thousandths place. Which calculation proves her statement?
Answer: If the digit is d, then 10d=10,000×0.001d shows this relationship correctly
When you encounter place value problems involving very large or small numbers, focus on understanding what each digit's position actually represents in terms of value.
Let's think through this step by step. If a digit d is in the tens place, its value is 10d. If the same digit d is in the thousandths place, its value is 0.001d (since thousandths means 10001). Ms. Chen claims the tens place value is 10,000 times larger than the thousandths place value.
To verify this relationship, we need: 10d=10,000×0.001d. Let's check: 10,000×0.001=10, so 10,000×0.001d=10d. This confirms the relationship is correct.
Choice A incorrectly uses 0.01d (hundredths) instead of 0.001d (thousandths), and uses 100 instead of 10 for the tens place value. Choice B makes the same error with hundredths place and incorrectly uses 1,000 as the multiplier instead of 10,000. Choice D uses 0.1d (tenths place) rather than thousandths, and the multiplier 100 is far too small.
Only choice C correctly represents both place values: 10d for tens place and 0.001d for thousandths place, with the accurate 10,000 multiplier.
Remember: When comparing place values, always convert the position to its decimal equivalent first (tens = ×10, thousandths = ×0.001), then check if the multiplication relationship holds true. - A recipe uses 2.5 cups of flour. In 2.5, the digit 2 is in the ones place and the digit 5 is in the tenths place (adjacent places). Which statement about the digit 5 is correct?
Answer: The digit 5 has a value of 0.5 because it is in the tenths place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 2.5, the digit 5 in the tenths place has a value of 0.5, which is 1/10 of the ones place. A common misconception is that tenths equal ones in value, but tenths are 0.1 times the digit. Place value enables comparison between whole and decimal parts of numbers. This understanding facilitates addition and subtraction across the decimal point.
- Maria writes the decimal 6.847 and notices that the 4 is in the hundredths place. She wants to write a new decimal where the digit 4 has a value that is 10 times greater. In which place should she put the 4 in her new decimal?
Answer: In the tenths place to increase the place value
In 6.847, the 4 represents 4 hundredths (0.04). To make it 10 times greater, it needs to represent 0.4 (4 tenths). Moving one place to the left (from hundredths to tenths) increases the value by a factor of 10.
- A store sign shows a price of 15.50. In 15.50, the digit 5 is in the tenths place and the digit 0 is in the hundredths place (adjacent places). If the digit 5 moved one place to the right, how would its value change?
Answer: Its value would become 101 as great.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 101 of the place immediately to its left. For example, in the number 15.50, moving the digit 5 from the tenths place (0.5) to the hundredths place changes its value to 0.05, which is 101 as great. A common misconception is that moving a digit doesn't change its value, but each shift right divides by 10. Place value allows us to understand how positions affect a number's overall value. This helps in comparing and ordering decimals effectively. - In the number 7,105.08, the digit 0 is in the tenths place and the digit 8 is in the hundredths place (adjacent places). Which statement about the value of the digit 8 is correct?
Answer: The digit 8 has a value of 0.08, which is 101 of 0.8 in the tenths place.
The value of a digit in a decimal number depends on its place relative to the decimal point. Each place value is 10 times the value of the place immediately to its right, meaning moving left multiplies the value by 10. Conversely, each place value is 1/10 of the value of the place immediately to its left, so moving right divides the value by 10. For example, in the number 7,105.08, the digit 8 in the hundredths place has a value of 0.08, which is 1/10 of the value a digit 8 would have in the tenths place at 0.8. A common misconception is that hundredths are larger than tenths because they sound more precise, but tenths are actually 10 times larger. Understanding place value relationships allows us to accurately compare decimals, such as recognizing 0.08 is smaller than 0.1. This knowledge also supports working with large numbers, like those in scientific or financial contexts, by clarifying decimal contributions. - A water bottle holds 0.606 liters. In 0.606, the first 6 is in the tenths place and the second 6 is in the thousandths place. Which statement correctly compares the value of the two digits 6?
Answer: The 6 in the tenths place is 100 times the value of the 6 in the thousandths place.
The value of a digit in a number depends on its position or place in the number. Each place value is 10 times greater than the place immediately to its right. Similarly, each place value is 1/10 of the place immediately to its left. For example, in the number 0.606, the 6 in the tenths place is worth 0.6, which is 100 times the 6 in the thousandths place at 0.006 since there are two places between them. A common misconception is that same digits have equal values regardless of position, but position determines the actual worth. Place value relationships allow us to compare digits across multiple positions by multiplying or dividing by 10 for each shift. This understanding is crucial for grasping the magnitude of numbers in decimal form.
- Two students are comparing decimals. Student A says: 'In 52.39, the 9 represents 9 hundredths.' Student B says: 'If I write 523.9, my 9 represents a value 100 times larger than your 9.' Is Student B correct, and why?
Answer: No, because the 9 in 523.9 is only 10 times larger than in 52.39
When comparing decimal place values, you need to understand how each position relates to the others. Each place value is exactly 10 times larger than the position to its right.
Let's examine what each 9 actually represents. In 52.39, the 9 is in the hundredths place, so it represents 9×0.01=0.09. In 523.9, the 9 is in the tenths place, so it represents 9×0.1=0.9.
To find how many times larger the second 9 is, divide: 0.9÷0.09=10. The 9 in 523.9 is only 10 times larger than the 9 in 52.39, making Student B incorrect.
Looking at the wrong answers: Choice A incorrectly states that tenths are 100 times larger than hundredths, when they're actually only 10 times larger. Choice B makes an even bigger error, claiming the difference is 1000 times. Choice C repeats the same mistake as A, incorrectly stating the relationship is exactly 100 times. All of these reflect a common misconception about decimal place value relationships.
Remember this pattern: each decimal place is exactly 10 times the value of the place to its right. Tenths are 10 times hundredths, hundredths are 10 times thousandths, and so on. When you move one place to the left, you multiply by 10, not 100. This consistent "times 10" relationship is key to mastering decimal comparisons.