First subtract the coupon amount from the price of the food: $7.50 - $2.50 = $<<7.5-2.5=5.00>>5.00
Then subtract 20% from 100% to find out what percentage of the reduced price Carla pays: 100% - 20% = 80%
Now multiply the price after the coupon by the percentage Carla pays to find the final price: $5.00 * .8 = $<<5*.8=4.00>>4.00
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