Quality Cleaners decides to raise the price of dry cleaning a vest from $5 to $6. The same percent increase is applied to dry cleaning a dress. The old cost of dry cleaning a dress is $12. What is the new cost of dry cleaning a dress?

Answer 1

The original price of dry cleaning a vest = $5
The new price of dry cleaning a vest = $6

The percentage increase is obtained by
new price-old price/old price × 100 = 20%
so there is a 20% increase in price.

applying this 20% increase to the cost of dry cleaning, the new cost will become

100+20/100 ×12
this is a 120% increase in cost.

mathematically this can be solved by
120/100×12 = $14.4

the new cost of dry cleaning is $14.4