Answer:
5 1/3 hours.
Explanation:
Ashley prepares 1 bag in 2/3 minutes.
One friend takes 2/3 + 3/4 * 2/3 = 7/6 minutes to make 1 bag.
4 of her friends can make 1 bag in 7/6 * 1/4 = 7/24 minutes.
If it takes x minutes for Ashley and 4 friends to make one bag then we have:
1 / 2/3 + 1 / 7/24 = 1 / x
3/2 + 24/7 = 1/x
Multiply through by 14x:
21x + 48x = 14
x = 14/69 minutes.
So the time to make 1575 bags = 1575 * 14/69
= 320 minutes.