John decides to start collecting art.  He pays the same price for his first 3 pieces of art and the total price came to $45,000.  The next piece of art was 50% more expensive than those.  How much did all the art cost?
The first 3 pieces each cost 45000/3=$
<gadget id="calculator">45000/3</gadget>
<output>15_000</output>
15,000.
So the next piece was 15,000*.5=$
<gadget id="calculator">15000*.5</gadget>
<output>7_500</output>
7,500 more expensive.
That means it cost 15,000+7,500=$
<gadget id="calculator">15000+7500</gadget>
<output>22_500</output>
22,500.
That means in total he spent 45,000+22,500=$67,500.

<result>67_500</result>