Question

when a number is divided by 9 the remainder is 7 . if twice the number is divided by 9 then remainder is ?

Answer 1

let x is the number when divided by 9 , remainder is 7

so , x = 9y + 7

now twice of its is , 2x

x + x = 9y + 7 + 9y + 7

twice of a number = 9 × 2y + 14

but , 14 = 9 × 1 + 5

so ,

twice of a number = 9 × 2y + 9 × 1 + 5

twice of a number = 9 × (2y+1) + 5

so remainder is 5

Answer 2

Answer:

Step-by-step explanation:

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