Indirect proportion

It takes two people ninety minutes to plant 66 flower bulbs. At this rate, how many bulbs could three people plant in three hours?

1 answer

We can start the problem by using ratios. Let x be the number of bulbs that three people can plant in three hours. Since the number of people and the time are changing, we can assume that the rate of planting (i.e. bulbs per minute) is constant.

The rate of planting for two people is:

66 bulbs / 90 minutes = 0.733 bulbs per minute

Using the same rate, the number of bulbs that three people can plant in one minute is:

x bulbs / (3 hours x 60 minutes) = 0.733 bulbs per minute

Simplifying this expression, we get:

x = 0.733 bulbs per minute x 3 hours x 60 minutes

x = 131.94 bulbs

Therefore, three people can plant about 132 bulbs in three hours.