Question

If a 10 digit n.o 2094x843y2 is divisible by 88 then value of 5x-7y at the largest possible value of x is

option
(A) 3
(B)5
(C)2
(D)6​

Answer 1

Answer:

1

If a 10-digit number 2094x843y2 is divisible by 88, then what is the value of 5x-7y for the largest possible value of x?

Earn an MBA degree from a premier university in India.

SusaiRaj

Answered July 11, 2019

If a number is to be divisible by 8 then the number formed by the last 3 digits should be divisible by 8.

If the number is to be divisible by 11 then the difference of the sum of the odd placed digits and even placed digits should be either 0 or divisible by 11.

If a number is to be divisible by 88, then it is to be divisible by both 8 and 11.

In the number 2094x843y2, sum of the even placed digits = 0+4+8+3+2= 17

Sum of the odd placed digits= 2+9+x+4+y = 15+x+y

So the difference between the above two is x+y-2..

If the number is to be divisible by 11, then x+y = 2 or 13. Since we need the max.value for x , we have to take x+y= 13. Now we have to find the minimum value possible for y. The value of y is > or = to 4 since the maximum possible value for x is 9.

If the number 3y2 is to be divisible by 8, then y should take the value 5. So then x = 13–5 = 8.

Now 5x - 7y= 5×8 - 7×5 = 40–35 = 5

mark me as brainlist