Question

WORK The ecology club is landscaping a local park. Dell can plant a flower bed in 3 hours. Max can plant a flower bed of the same size in 4 hours. a. Using t, time in hours, write an expression representing how many flower beds they will complete in t hours working together.

Answer 1

Explanation:

this simply means that Dell can do 1/3 of the work in 1 hour, and Max can do 1/4 of the work in 1 hour.

so, working together, they can complete 1/3 + 1/4 of the work in 1 hour.

to really add these fractions, we need to bring them to the same denominator by finding the smallest (or lowest) common multiple of the existing denominators, which is in this very simple case just 3×4 = 12

1/3 + 1/4 = 4/12 + 3/12 = 7/12

therefore, together they can complete 7/12 of a flower bed in 1 hour.

so, by defining the variable fb as the number of completed flower beds :

fb = 7/12 × t