Question

The sum of the 2digits of a number is 7. If the digits are reversed, the new
number is increased by 3 equals 4 times the original number. Find the original number?​

Answer 1

Answer:

Original number is 16.

Step-by-step explanation:

Let the digits be x and y.

x + y = 7

x = 7 - y.....(i)

The number is 10x + y.

The new number is 10y + x (with reversed digits).

10y + x + 3 = 4(10x + y)

10y + x + 3 = 40x + 4y

6y + 3 = 39x

on substitution,

6y + 3 = 39(7 - y)

6y + 3 = 273 - 39y

45y = 270

y = 6

x = 7 - y

x = 1

Original number is 16.