If 345 A 7 is divisible by 3,supply the missing digit in place of ‘A

1.	If 345 A 7 is divisible by 3,supply the missing digit in place of ‘A’.
Answer» If the sum of the digits of a number is divisible by 3, then the number is divisible by 3. ∴ 345A7 ⇒ 3 + 4 + 5 + A + 7 = 19 + A 19 + A = 3 x 7 ⇒ A = 21 – 19 = 2 ⇒ A = 24 – 19 = 5 A + 19 = 3 x 8 ⇒ A = 24 – 19 = 5 A + 19 = 3 x 9 ⇒ A = 27 – 19 = 8 ∴ A = {2,5,8}

If 345 A 7 is divisible by 3,supply the missing digit in place of ‘A’.

Answer»

If the sum of the digits of a number is divisible by 3, then the number is divisible by 3.

∴ 345A7 ⇒ 3 + 4 + 5 + A + 7 = 19 + A 19 + A = 3 x 7

⇒ A = 21 – 19 = 2 ⇒ A = 24 – 19 = 5

A + 19 = 3 x 8

⇒ A = 24 – 19 = 5

A + 19 = 3 x 9

⇒ A = 27 – 19 = 8

∴ A = {2,5,8}