Respuesta :
The amount that William would save by paying cash instead of credit card is $1
What is a Discount?
This refers to the amount deducted from the value of a certain commodity so that there would be a reduced price for the good.
Hence, given that there is a discount of $0.05 per gallon if you pay with cash
William fills 20 gallons of gas
The amount saved by paying cash by William would be 0.05 * 20 = $1
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