John repairs 5 cars.  3 of the cars take 40 minutes each to repair.  The remaining ones take 50% longer each to repair.  He makes $20 per hour repairing cars.  How much money does he make?
The 3 cars take 3*40=
<gadget id="calculator">3*40</gadget>
<output>120</output>
120 minutes to make.
He repairs 5-3=
<gadget id="calculator">5-3</gadget>
<output>2</output>
2 more cars.
They each take 40*.5=
<gadget id="calculator">40*.5</gadget>
<output>20</output>
20 minutes longer per car.
So they each take 40+20=
<gadget id="calculator">40+20</gadget>
<output>60</output>
60 minutes.
So he repaired cars for 120+2*60=
<gadget id="calculator">120+2*60</gadget>
<output>240</output>
240 minutes.
That is 240/60=
<gadget id="calculator">240/60</gadget>
<output>4</output>
4 hours.
So he made 4*20=$
<gadget id="calculator">4*20</gadget>
<output>80</output>
80.

<result>80</result>