Question

1.Mr Sim bought new tv at a discounted price of 15%.He paid $836, inclusive of 3% GST(goods and services tax. What was the original price of the tv?

2.How to calculate original price before GST and before discount? What is the formula? Tks

Answer 1

original price = p
discounted price = 0.85 p
tax = .03(.85 p) = .0255 p
so
836 = .85 p + .0255 p = .8755 p
p = 954.88

check
.85 * 954.88 = 811.65
811.65*1.03 = 836 good