Stefan picks up 40 bushels of apples in 12 hours.
With the helo of gabriela they do so th 6.67 hours. We can represent this in the following table:
Bulshels of apples Hours
40 6.67
We need to multiply these number by 2, so that we can know how much time it would take for Gabriella to pick 40 alone.
Bulshels of apples Hours
40 6.67
80 13.34
Now, since picking 80 together takes 13.34 hours, and we know that tefan picks up 40 in 12 hours, the other 40 where picked up by Gabriella in:
[tex]13.34-12=1.34[/tex]Answer: 1.34 Hours