Sum of the digits in the product (16^100) * (125^135) ?
2024
Sum of the digits in the product (16^100) * (125^135) ?
- A.
8
- B.
18
- C.
11
- D.
110
Attempted by 2073 students.
Show answer & explanation
Correct answer: C
Solution: compute the product and sum its digits.
Express the bases as powers of primes: 16^100 = (2^4)^100 = 2^400, and 125^135 = (5^3)^135 = 5^405.
Combine the powers: 2^400 * 5^405 = 2^400 * 5^400 * 5^5 = 10^400 * 3125.
So the product equals 3125 followed by 400 zeros.
Therefore the sum of the digits is 3 + 1 + 2 + 5 = 11.