12% as a fraction is 12/100 but it’s simplest form is 3/25
5x2 would be 10 and 10-50x would be negative 40x and 40x + 125 would be 165x
It seems most likely that ...
... Samantha will save $37.50 because she must first find the 25% sale price before taking the extra 50% reduction
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In the real world, it seems probable that Samantha will be offered the choice of using the coupon <em>or</em> the sale discount. If she chooses tht 50% coupon, her savings will be $30. If she chooses the marked sale discount, her savings will be $15.
The scenario above assumes she gets 50% off the sale price of $45, so saves $15+22.50 = $37.50 off the original price.
