Question

If an 8-digit number 30x0867y is divisible by 88, then what is the value of (3x+y)?

Answer 1

Value of (3x+y)=5.

Step-by-step explanation:

A number is divisible by 88 ,if it is divisble by 11 and 8.

Divisiblity test for 8:

Last three digit are divisible by 8

So,if we put y=2

then 672 is divisible by 8.

Divisiblity test for 11:

(sum of odd place digits )-(sum of even place digits)= 11 or multiple of 11

(7+8+x+3)-(2+6+0+0)= 11

(18+x) -8=11

18+x-8=11

10+x=11  

x=11-10

x=1

Now,(3x+y)=$(3\times 1+2)$

       (3x+y)=3+2

     (3x+y)=5

So,value of (3x+y)=5.