Respuesta :

We use proportion in this problem solving.
We know that 100% = 40.00 and 125%=x
I take 125% because the marks the price up 25%. So it is 100%+25%.
100x=40.00×125
x=40.00×125÷100
x=50.00
So the she sells the cell phone at 50.00

Answer:

Well the answer is 50 because 25 percent of 40 is 10 so since she is marking it up you need to add the ten and not subtract it.

Step-by-step explanation: