Explanation:
48 oranges in 5 minutes means she picked 48 oranges in 300 seconds.
Divide 48 by 300 to get what she would pick in one second.
This equals 0.16
Multiply 0.16 by 120 seconds [how many seconds are in two minutes].
This equals 19.2 oranges in two minutes. As she cannot pick 0.2 of an orange, she could pick 19.