Q15 REPRESENTATIONS
The digits of a three-digit number A are written in the reverse order to form another three-digit number B. If B > A and B-A is perfectly divisible by 7, then which of the following is necessarily true?
a. 100< A<299
b. 106<A <305
c. 112<A <311
d. 118< A <317
Let A = 100x + 10y + z and B = 100z + 10y + x .
According to given condition B - A = 99(z - x)
As (B - A) is divisible by 7 .
So clearly (z - x) should be divisible by 7.
z and x can have values 8,1 or 9,2 , such that 8-1=9-2=7 and y can have value from 0 to 9.
So Lowest possible value of A lowest x,y and z which is is 108 and the highest possible value of A is 299Write Here