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 = $
<gadget id="calculator">4*7</gadget>
<output>28</output>
28.
Double layer cake slices cost $7 x 5 = $
<gadget id="calculator">7*5</gadget>
<output>35</output>
35.
All the cake slices together cost $28 + $35 = $
<gadget id="calculator">28+35</gadget>
<output>63</output>
63.
He will receive change of $100 - $63 = $
<gadget id="calculator">100-63</gadget>
<output>37</output>
37.

<result>37</result>