Gabriela bought a new pair of glasses at the store when they were having a 30%30/% 30% 30, percent off sale. If the regular price of the pair of glasses was $72/$72 $72 dollar sign, 72, how much did Gabriela pay with the discount?

Since the glasses are 30% off, Garbriela will pay 100% - 30% of the original price, or 70%.

Therefore, Gabriela will pay $72 * 0.7 = $50.40.

The value of the discount may be calculated instead. Moving the decimal one place to the left would quickly yield the value of a 10% discount, $7.20. A 30% discount is three times that, or $21.60. Then we subtract this value from the original price of $72.

$72.00 - $21.60 = $50.40

The final price Gabriela pays is $50.40.

For this case you can solve the problem by a simple rule of three:

72 - - - > 100%

x - - - > 30%

Clearing x we have:

x = (30/100) * (72) = 21.6 $

Then, we must subtract this value from the original price:

72-21.6 = 50.4 $

answer:

Gabriela pays $ 50.4 with the discount