There were 12 cookies in the first batch.
Each of the children ate 6 cookies in all (3 from each batch).
Work backward.
 At the end, there were 4 cookies left on the tray.
 Each of the children ate 3 cookies from the second batch.
4 x 3 = 12
 Add the 12 cookies they ate to the 4 cookies left on the tray.
12 cookies + 4 cookies = 16 cookies
 Mr. Ortiz ate 2 cookies.
Add: 2 + 16 = 18
 6 cookies crumbled. Add: 18 + 6 = 24
 There were 24 cookies in the second batch.
 The second batch was twice as big as the first batch; 24 ÷ 2 = 12
 There were 12 cookies in the first batch.
 To find the number of cookies each child ate in the first batch; Divide 12 cookies by 4 children: Each child ate 3 cookies.
 3 cookies from the first batch + 3 cookies from the second batch = 6 cookies for each child.
