You went shopping and found a pair of shoes that were $45.00 on sale for $27.50. what was the percent of decrease of the shoes? your answer should go 1 decimal place)

Percent decrease = (original number - new number) / original number* 100
                             = (45 - 27.5) / 45* 100
                             = 17.5 / 45* 100
                             = 0.3888 * 100 
                             = 38.9 % decrease <== thats rounded

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121 pints. they had 176 and drank 55