It takes 32 hours for Tim’s painting to be better deal.
Given, Shirley is going to have the exterior of her home painted
Tim’s painting charges plus per hour
Colorful pens charges per hour
We have to find required hours for Tim’s painting to be the better deal . Let the number hours be h. So, Tim’s charges = colorful pens charges
Now, Let us check charges after 32 hours.
So, at 31 hours colorful pens are economical but at 32 hours Tim painting is economical.
2 x 40 = 80