Theo can eat 13 cookies, 3 times a day, 20 days each month. How many cookies can he eat in 3 months?
The total amount of cookies he can eat in a day is 13 x 3 = 
<gadget id="calculator">13*3</gadget>
<output>39</output>
39.
The total amount of cookies he can eat in a month is 39 x 20 = 
<gadget id="calculator">39*20</gadget>
<output>780</output>
780.
Therefore, the total amount of cookies he can eat in 3 months is 780 x 3 = 
<gadget id="calculator">780*3</gadget>
<output>2_340</output>
2340.

<result>2_340</result>