According to the order of operations (PEMDAS/BODMAS), first evaluate the expressions inside the parentheses. Within the parentheses, perform multiplication and division from left to right. \(25 \times 4 = 100\) and \(50 \div 2 = 25\). Now, perform the addition inside the parentheses: \(100 + 25 = 125\). Finally, perform the subtraction: \(300 - 125 = 175\).

This question tests middle school students' fluency in the four basic operations: addition, subtraction, multiplication, and division. Mastery of these operations is crucial for solving real-world problems and is foundational for higher-level math concepts. In this specific problem, students are asked to multiply the cost per shirt by four to find the total cost. The correct answer, $29.00, is obtained by accurately performing the multiplication, demonstrating an understanding of multiplying decimals. A common mistake, such as $28.00, occurs when students forget to account for the cents properly. To improve, students should practice identifying the operation required by a problem and double-check computations for errors. Teaching strategies include using visual aids, such as number lines or grids, and providing step-by-step problem-solving frameworks.

This question tests middle school students' fluency in the four basic operations: addition, subtraction, multiplication, and division. Mastery of these operations is crucial for solving real-world problems and is foundational for higher-level math concepts. In this specific problem, students are asked to subtract the discount from the original price to find the new price. The correct answer, $39.99, is obtained by accurately performing the subtraction, demonstrating an understanding of decimal places in money. A common mistake, such as $59.99, occurs when students add instead of subtract. To improve, students should practice identifying the operation required by a problem and double-check computations for errors. Teaching strategies include using visual aids, such as number lines or grids, and providing step-by-step problem-solving frameworks.

This question tests middle school students' fluency in the four basic operations: addition, subtraction, multiplication, and division. Mastery of these operations is crucial for solving real-world problems and is foundational for higher-level math concepts. In this specific problem, students are asked to multiply the cost per hat by three to find the total cost. The correct answer, $29.40, is obtained by accurately performing the multiplication, demonstrating an understanding of carrying over in decimals. A common mistake, such as $19.60, occurs when students multiply by two instead of three. To improve, students should practice identifying the operation required by a problem and double-check computations for errors. Teaching strategies include using visual aids, such as number lines or grids, and providing step-by-step problem-solving frameworks.

This problem is best solved by working backward. Daniel has $40 left, which is half of the money he had before giving some to his brother. So, before giving money to his brother, he had \($40 \times 2 = $80\). This $80 was the amount remaining after he spent $25 on a book. To find his initial amount, add the $25 back: \($80 + $25 = $105\).

First, find the total number of bookshelves in the library by multiplying the number of floors by the number of bookshelves per floor: \(3 \times 40 = 120\) bookshelves. Then, find the total number of books by multiplying the total number of bookshelves by the number of books per bookshelf: \(120 \times 150 = 18,000\) books.

First, find the total amount of grain sold: \(825 + 1150 = 1975\) pounds. Next, find the amount of remaining grain by subtracting the amount sold from the starting amount: \(2500 - 1975 = 525\) pounds. Finally, divide the remaining grain by the number of bags: \(525 \div 25 = 21\) pounds per bag.

Follow the operations in order. First, multiply 100 by 4: \(100 \times 4 = 400\). Second, subtract 60 from the result: \(400 - 60 = 340\). Third, divide this result by 2: \(340 \div 2 = 170\). Finally, add 15 to this result: \(170 + 15 = 185\).

First, determine the scaling factor for the recipe. You want to make 90 cookies instead of 12. The scaling factor is \(90 \div 12 = 7.5\). Now, multiply the amount of flour by this scaling factor: \(2 \text{ cups} \times 7.5 = 15\) cups. Alternatively, find how many cookies one cup of flour makes: \(12 \div 2 = 6\) cookies per cup. Then divide the desired number of cookies by this rate: \(90 \div 6 = 15\) cups.

First, calculate the number of students in the first seven classrooms: \(7 \times 24 = 168\) students. Next, find the number of remaining classrooms: \(15 - 7 = 8\) classrooms. Then, calculate the number of students in these remaining classrooms: \(8 \times 27 = 216\) students. Finally, add the student totals from both groups of classrooms to find the total number of students in the school: \(168 + 216 = 384\) students.