Dena has a coupon for 20% off a single purchase at a store. if the item she buys cost p dollars, then the amount she will be charged is represented by the expression below.
p-0.2p
a.-0.2p
b.0.8p
c.1.2p
d.1.8p

The decimal equivalent of the given percentage is 0.20. When an item is at 20% off, this means that its value becomes only 80% of the original. The decimal equivalent of this number is 0.80. This means that Dena will have to be charged only 0.80p. The answer is letter B. 

The first one is correct