Question

If 21y5 is a multiple of 9 where y is a digit what is the value of y
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Answer 1

Answer:

y = 1

Step-by-step explanation:

because according to divisibilty rule of 9

sum of all the digit of a number is divisible by 9 ... then that number is divisible by 9

Answer 2

Answer:

1

Step-by-step explanation:

we know that,

Any multiple of 9 has sum of its digits equal to its factors.

Here,

2+1+y+5=9(nearest factor of 9)

y=9-8

y=1