Math · Pre-Algebra
Evaluating an Exponent
Medium
Math
Pre-Algebra
Question
What is the value of 5^3?
Answer choices
- 125
- 120
- 130
- 15
- 625
A Correct answer: A) 125
Set up the problem carefully before computing. Compute the repeated multiplication step by step. Do not multiply base by exponent — that is a common error.
Carry the arithmetic through one step at a time, double-checking signs and units. The ACT writes wrong answers to catch the most common slips, so an answer that "looks right" without verification is risky.
Plug the answer back into the original expression as a sanity check whenever the problem allows. If the substitution does not balance, you have made an arithmetic mistake earlier in the work.
The underlying rule
5^3 means 5 multiplied by itself 3 times. 5 × 5 × 5 = 125.
Why each wrong answer is wrong
- B) 120: A common arithmetic or sign error leads to this value; carefully redo the calculation.
- C) 130: A common arithmetic or sign error leads to this value; carefully redo the calculation.
- D) 15: A common arithmetic or sign error leads to this value; carefully redo the calculation.
- E) 625: A common arithmetic or sign error leads to this value; carefully redo the calculation.
Study tip
Exponents are repeated multiplication, not multiplication of the base by the exponent. 2^3 = 8, not 6.
More Medium Pre-Algebra
- Percent of a NumberWhat is 40% of 150?
- Splitting a Total in a RatioA total of 300 dollars is divided between two people in the ratio 5:10. How much does the
- Mean of a Data SetFind the mean of the data set: 8, 6, 9, 12, 12.
- Evaluating an ExponentWhat is the value of 2^3?
- Adding Fractions with Different DenominatorsCompute 2/6 + 3/4. Express the answer in lowest terms.