If the 8- digit number 7x5739y2 is divisible by 88, then the largest possible value of (4x + 3y) is :
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 51.
If the number is divisible by 88, that means it is divisible by both 8 and 11.
Divisibility rule of 8: When the last three digits of a number is divisible by 8, the number is divisible by 8.
Divisibility rule of 11: If the difference between the sum of the digits at the odd places and the sum of the digits at the even places of the number is either zero or a multiple of 11, then the number is divisible by 11.
Given, 7x5739y2
To make it divisible by 8, y = 9
Now, difference of sum of odd and even places of digits = (7 + 5 + 3 + y) - (x + 7 + 9 + 2)
⇒ 24 - 18 - x = 0
⇒ x = 6
Required answer = 4(6) + 3(9)
⇒ 24 + 27 = 51