so, if the discount was 5%, then the sale prize was equal to 95% of the original prize
so 68.40=0.95*x
we divide both sides by 0.95. Let;s start by multiplying them by 100:
6840=95*x
divide by 5 both sides:
1368=19x
now divide by 19
72=x
so the original prize was 72.
