Direct and inverse variation

4 workers can do the job in 18 days.

Step-by-step explanation:

The number of days d varies inversely as the number of workers.

We can write it as:

where k is constant of proportionality

We are given: If it takes 9 days for 8 workers to complete the job, then how many workers would it take to do the job in 18 days.

d = 9, w = 8

d = 18, w =?

First we will find value of k when d = 9, w =8

The value of k, will remain same as it is constant.

We get k = 72.

So, Now we have d = 18, k = 72 and we need to find w

So, 4 workers can do the job in 18 days.

i think c. but don't trust it.

step-by-step explanation:

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: