Question

The sum of the digits of a two-digit number
is 7. When the digits are interchanged, the
reversed number is 5 times the ten's digit
of the original number. Find the original
number.
With explanation

Answer 1

Step-by-step explanation:

Let the units digit be x.

The tens digit =7−x.

Original no. =10(7−x)+x=70−9x

If digits are reversed, no. =10x+7−x=9x+7

9x+7−2=2(70−9x)

9x+5=140−18x

27x=135

x=5

Tens digit =7−5=2

Number =25