Correct option is C
Given :
8-digit number = 43x259y2
It is divisible by 88.
Options given for x, y, and we have to find which is NOT true.
Concept Used:
Divisibility by 11
Rule:
(Sum of digits at odd places) - (Sum of digits at even places) = 0 or multiple of 11
Solution :
Divisibility by 8
A number is divisible by 8 if its last 3 digits are divisible by 8.
Last 3 digits = 9y2
Check for given options:
y = 1
y = 9
y = 5
All options satisfy divisibility by 8.
Number: 4 3 x 2 5 9 y 2
Odd places: 4 + x + 5 + y = 9 + x + y
Even places: 3 + 2 + 9 + 2 = 16
Difference:
(9 + x + y) - 16 = x + y - 7
For divisibility by 11:
x + y - 7 = 0
Check options:
Option | x + y | x + y − 7 | Divisible by 11 |
|---|---|---|---|
(a) x= 6, y = 1 | 7 | 0 | right |
(b) x = 9, y = 9 | 18 | 11 | right |
(c) x = 4, y = 1 | 5 | −2 | wrong |
(d) x = 2, y = 5 | 7 | 0 | right |
Answer :
Option (c): x = 4 and y = 1 is NOT true.