Question

solve this sums answer me step-by-step​

Answer 1

if a number divisible by 9 then sum of the digits is divisible by 9 so,

2+1+y+5 = 8+y

if 8+y is divisible by 9 then y = 1,10,19 and so on

but y=1 is only possible because 1 is a single digit but 10,19 like that numbers have 2 digits