A two-digit number is seven times the sum of its digits, If each digit is increased by 2, the number thus obtained is 4 more than six times the sum of its digits, Find the number?
Correct Answer: 42
Explanation:
Let the two-digit number be 10x + y
10x + y = 7(x + y)
⇒ x = 2y ...(i) 10(x +2 ) + (y + 2) = 6(x + y + 4) + 4
or 10x + y + 22 = 6x + 6y + 28
⇒ 4x - 5y = 6 ...(ii) Solving equations (i) and (ii)
We get x = 4 and y = 2
