Which of the following numbers is divisible by 55?
2025
Which of the following numbers is divisible by 55?
Answer: A. 899250 — A number is divisible by 55 = 5 x 11 only when it is divisible by BOTH 5 and 11 at once. Divisibility by 5 needs the last digit to be 0 or 5. Divisibility by…
- A.
899250
- B.
899493
- C.
899122
- D.
898405
Attempted by 210 students.
Show answer & explanation
Correct answer: A
A number is divisible by 55 = 5 x 11 only when it is divisible by BOTH 5 and 11 at once. Divisibility by 5 needs the last digit to be 0 or 5. Divisibility by 11 needs the difference between the sum of digits in the odd places and the sum of digits in the even places (counted from the right) to be 0 or a multiple of 11.
Apply both tests to every option:
Number | Last digit | Divisible by 5? | Alternating digit-sum (11-test) | Divisible by 55? |
|---|---|---|---|---|
899250 | 0 | Yes | 11 (a multiple of 11) | Yes |
899493 | 3 | No | not tested (fails 5-test already) | No |
899122 | 2 | No | not tested (fails 5-test already) | No |
898405 | 5 | Yes | 2 (not a multiple of 11) | No |
Independent check: 899250 divided by 55 gives exactly 16350, since 55 x 16350 = 899250, confirming the result with no remainder.
So 899250 is the number divisible by 55.