Answer:
60 minutes
Explanation:
She painted 2/5 of the wall.
She still needs to paint 3/5 of the wall.
3 is 50% more than 2, so 3/5 is 1.5 times 2/5, so it will take her 1.5 times the time it took so far.
1.5 * 40 minutes = 60 minutes.
Answer: 60 minutes