If the TV is 70% off, then that means she paid 30% of the original cost. If 30% of the original cost is $120, then...
30% * x = 120
.30x = 120
x = 120/.30
x = 400
The original cost was $400
you just have to move the decimal point 9 places to the right thats an easy trick to remember 1849900000
