Question 152108
The units digit of a two digit number is 1/2 the tens digit. If the digits are reversed, the sum of the new number and the original number is 132. Find the original number.
:
Let x = the 10's digit
Let y = the units digit
;
The number: 10x + y
:
Write an equation for each statement:
"The units digit of a two digit number is 1/2 the tens digit."
x = 2y
:
" If the digits are reversed, the sum of the new number and the original number is 132."
(10y + x) + (10x + y) = 132
:
11y + 11x = 132
:
Simplify, divide each term by 11
y + x = 12
:
Subsitute 2y for x
y + 2y = 12
y = {{{12/3}}}
y = 4
then
x = 8
:
The number: 84
:
Check solution: 48 + 84 = 132