At the patisserie, a single layer cake slice is $4 and a double layer cake slice is $7.  Dusty buys 7 single layer cake slices and 5 double layer cake slices.  If he pays with a $100 bill, how much change does he receive?
Single layer cake slices cost $4 x 7 = $<<4*7=28>>28.
Double layer cake slices cost $7 x 5 = $<<7*5=35>>35.
All the cake slices together cost $28 + $35 = $<<28+35=63>>63.
He will receive change of $100 - $63 = $<<100-63=37>>37.
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