Question #433bf

1 Answer
Nov 5, 2017

38

Explanation:

Let
x = ones digit
y = tens digit

the original number = 10y+x
the new number = 10x+y

We also know that:
x+y=11
Rearranging,
x=11y

The statement: "the new number is 45 more than the original number" can be mathematically written as:
10x+y=10y+x+45

Writing x in terms of y,
10(11y)+y=10y+(11y)+45
11010y+y=10y+11y+45
10y+y10y+y=110+11+45
18y=54
y=3

x=11y
x=113
x=8

Therefore, the original number is 38