Let's call the number of people working as "p" and the time it takes as "t". We know that with 15 people, it takes 2 hours to plant 450 tomatoes, so we can write:
15 people * t = 450 tomatoes
t = 450 / 15 = 30 minutes = 0.5 hours
If 5 more people are hired, there will be a total of 15 + 5 = 20 people working. To find the new time it takes to plant 450 tomatoes, we can rearrange the formula to solve for t:
t = 450 / (15 + 5) = 450 / 20
t = 22.5 minutes = 0.375 hours
So, with 20 people, it will take 0.375 hours to plant 450 tomatoes