Peter bought 4 new notebooks for school. 2 of them are green, one is black and the other one is pink. The total cost was $45. If the black notebook cost $15, and the pink one cost $10, how much did the green notebooks cost each?
The black and pink notebook cost a total of $15 + $10 = $
<gadget id="calculator">15+10</gadget>
<output>25</output>
25.
The green notebooks cost a total of $45 - $25 = $
<gadget id="calculator">45-25</gadget>
<output>20</output>
20.
Each green notebook cost $20 / 2 = $
<gadget id="calculator">20/2</gadget>
<output>10</output>
10.

<result>10</result>