ACT Math : How to use scientific notation

Study concepts, example questions & explanations for ACT Math

varsity tutors app store varsity tutors android store varsity tutors amazon store varsity tutors ibooks store

Example Questions

← Previous 1

Example Question #1 : Other Exponents

What is the sum of the solutions of the equation x2-2x-8=0?

 

Possible Answers:

-6

-10

2

6

-2

Correct answer:

2

Explanation:

The equation factors to (x-4)(x+2)=0, indicating that the roots are x=-2,4. The sum of these two roots is 2.

 

 

Example Question #2 : How To Use Scientific Notation

What is the number 350,000,000 in scientific notation?

Possible Answers:

3.5 x 109

3.5 x 106

3.5 x 105

3.5 x 108

3.5 x 107

Correct answer:

3.5 x 108

Explanation:

350,000,000 = 3.5 x 108 (exponent is equal to the number of decimal points shifted)

Example Question #3 : How To Use Scientific Notation

Given the equation 2xy + 4x² - y = 2x, if x = 2, what does y equal?

Possible Answers:

0

4

-4

2

Correct answer:

-4

Explanation:

We plug in the value given for x and solve for y. 

2xy + 4x² - y = 2x

2(2)y + 4(2)² - y = 2(2)

4y + 4(4) - y = 4

4y - y + 16 = 4

3y = -12

y = -4

Example Question #2 : Other Exponents

How do you express 657,800 in scientific notation?

Possible Answers:

6.578 × 103

65.78 × 106

65.78 × 104

65.78 × 103

6.578 × 104

Correct answer:

65.78 × 104

Explanation:

657800 = 6.578 × 105

OR

657800 = 65.78 × 104

Exponent on 10 is the number of decimal points over the number has shifted.

Example Question #5 : How To Use Scientific Notation

2 × 100 + 3 × 102 + 4 × 104 = ?

Possible Answers:

4,032

400,032

432

40,302

40,320

Correct answer:

40,302

Explanation:

2 × 100 + 3 × 102 + 4 × 104 =

2 + 300 + 40,000 = 40,302

Example Question #174 : Exponents

Give this number in scientific notation:

Possible Answers:

Correct answer:

Explanation:

There are six zeros and two more number places, for a total of eight, so 125,000,000 is equivalent to .

Example Question #3 : Other Exponents

Simplify the following expression:

 

Possible Answers:

Correct answer:

Explanation:

 

 

Example Question #8 : How To Use Scientific Notation

What is the number \dpi{100} \small 256,000,000,000 in scientific notation?

Possible Answers:

\dpi{100} \small 2.56\times 10^{12}

\dpi{100} \small 2.56\times 10^{10}

\dpi{100} \small 2.56\times 10^{13}

\dpi{100} \small 2.56\times 10^{9}

\dpi{100} \small 2.56\times 10^{11}

Correct answer:

\dpi{100} \small 2.56\times 10^{11}

Explanation:

\dpi{100} \small 256,000,000,000 = 2.56\times 10^{11} 

The exponent is equal to the number of decimal points shifted.

Example Question #643 : Algebra

Convert from scientific to decimal notation:

Possible Answers:

Correct answer:

Explanation:

In this case the exponent is positive hence you have to move the decimal point 4 places to the right from where it is in the problem giving us

Example Question #1 : How To Use Scientific Notation

Convert from decimal to scientific notation:

 

Possible Answers:

Correct answer:

Explanation:

In this case you have to move the decimal point 6 places to the right. When you move the decimal point to the right the exponent becomes negative.  Similarly when you move the decimal point to the left the exponent is positive.  Also, to the left of the decimal place there can be only one digit.

← Previous 1
Learning Tools by Varsity Tutors

Incompatible Browser

Please upgrade or download one of the following browsers to use Instant Tutoring: