The popcorn costs 8 - 3 = $<<8-3=5>>5.
The drink costs 5 + 1 = $<<5+1=6>>6.
The candy costs 6 / 2 = $<<6/2=3>>3.
The normal price is 8 + 5 + 6 + 3 = $<<8+5+6+3=22>>22.
Thus, the deal saves a customer 22 - 20 = $<<22-20=2>>2.
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