If 5^a = 3125, find the value of 5^(a − 3).
Aptitude
Surds and Indices
Difficulty: Easy
Choose an option
-
A5
-
B25
-
C125
-
D625
Answer
Correct Answer: 25
Explanation
Given data
- 5^a = 3125
Concept / Approach
- Express 3125 as a power of 5 and then reduce the exponent.
Step-by-step calculation3125 = 5^5 ⇒ a = 55^(a − 3) = 5^(5 − 3) = 5^2 = 25
Common pitfalls
- Confusing 5a with 5^a. The problem states an exponential equation 5^a = 3125.
Final Answer25