Question

Michelle asked Simon to take the largest 4 digit odd number, where each digit is unique and factorize it. Simon got an incorrect solution, so Michelle gave the correct solution. Which among the following can be Michelle's answer?

• A. 5 × 5 × 79 × 79
• B. 5 × 5 × 5 × 79
• C. 5 × 5 × 79
• D. 79 × 2 × 5 × 5

Answer 1

The correct option is B 5 × 5 × 5 × 79

The largest 4 digit odd number with all the unique digit will be 9875.
When we factorize this number we will get:
9875 = 5 × 5 × 5 × 79 (All the numbers are prime numbers)