Question

The number 325325 is divisible by:

• A. 7 and 19
• B. 19 and 13
• C. 23 and 13
• D. 11 and 13

Hint:

To check divisibility by 11, alternate sum and difference of the digits. For 13, simply divide the number to check for divisibility.

Answer 1

The Correct Option is D

To find the factors of 325325, we can use the divisibility rules. Step 1: Check divisibility by 11.
For divisibility by 11, take the difference between the sum of digits at odd positions and the sum of digits at even positions.
The digits of 325325 are 3, 2, 5, 3, 2, 5.
Sum of digits at odd positions = \( 3 + 5 + 2 = 10 \)
Sum of digits at even positions = \( 2 + 3 + 5 = 10 \)
The difference is \( 10 - 10 = 0 \), which is divisible by 11.
Thus, 325325 is divisible by 11. Step 2: Check divisibility by 13.
We can divide 325325 by 13 to check: \[ 325325 \div 13 = 25025, \] which is an integer. Therefore, 325325 is divisible by 13. Thus, the number 325325 is divisible by 11 and 13.