Michael and Thomas are selling their lego collections. They agree to split any money they earn. They sell them based on how many circles are on top. Each circle costs 1 cent. They earned $5 each after selling 100 single pieces, 45 double pieces, 50 triple pieces and a number of quadruple pieces. How many quadruple pieces did they sell?
They made $10 because 2 x 5 = 
<gadget id="calculator">2*5</gadget>
<output>10</output>
10.
They made $1 off single pieces because 100 x .01 = 
<gadget id="calculator">100*.01</gadget>
<output>1</output>
1.
They made $.9 off double pieces because 45 x .02 = 
<gadget id="calculator">45*.02</gadget>
<output>0.9</output>
.9.
They made $1.5 off triple pieces because 50 x .03 = 
<gadget id="calculator">50*.03</gadget>
<output>1.5</output>
1.5.
They earned $3.4 off the first three types because 1 + .9 + 1.5 = 
<gadget id="calculator">1+.9+1.5</gadget>
<output>3.4</output>
3.4.
They earned $6.6 off the quadruple pieces because 10 - 3.4 = 
<gadget id="calculator">10-3.4</gadget>
<output>6.6</output>
6.6.
They sold 165 quadruple pieces because 6.6 / .04 = 
<gadget id="calculator">6.6/.04</gadget>
<output>165</output>
165.

<result>165</result>