Answer:
10 pull
As 48 seconds + 20 seconds push = 68 seconds
Explanation:
Because she did 10 push = 20 seconds = 2 seconds each
12 pull = 48 seconds = 4 seconds each
= 68 seconds combined.
Workings;
18 seconds found for the first set
We then find a divider of 68 and know that
6 x 3 = 18 seconds push
12 x 3 =36 seconds pull T= 54
14 left over = 1 x 12 seconds pull
+ 2 seconds push
= 10 push = 20 seconds combined.
= 12 pull = 48 seconds combined.
68/24 = 2.8- so 14 x 2 = 28 and 10 x 4 = 40 so the answer is 14 push and 10 pull