James decides to pick some blueberries.  It cost $20 to go picking and then another $1.5 per pound.  He picked 30 pounds of blueberries.  How much did he save compared to buying at the store for $2.5 a pound?
He paid 30*1.5=$
<gadget id="calculator">30*1.5</gadget>
<output>45</output>
45 for the blueberries he picked.
So after the entrance fee it was 45+20=$
<gadget id="calculator">45+20</gadget>
<output>65</output>
65.
To buy them at the grocery store it would cost 30*2.5=$
<gadget id="calculator">30*2.5</gadget>
<output>75</output>
75.
So he saved 75-65=$
<gadget id="calculator">75-65</gadget>
<output>10</output>
10.

<result>10</result>