N- a number
The sum of 18 and a number: 18 + n
125 x .15 = 18.75
18.75 + 125 = 143.75
or
125 x 1.15 = 143.75
both work
the second method is easier (works for tax and tips)
The discount price is &78.75
D=2.r
3.6m=2r
3.6m DIVITE BY 2=1.8
Answer it is (d) 1.8