It takes 18 electricians 35 days to wire a new housing subdivision. How many days would 28 electricians require to do the same job?

18 Electricians can complete the wiring in 28 days. We are to find how days will 28 electricians take for the same task.

Note that, if the number of electricians are increased, the number of days will be less to complete the same job. So we can conclude that there is an inverse relation between the Electricians and the number of days.

Let 28 electricians take x days to complete the same task. In an inverse relation, the product of two quantities is always equal to the constant of proportionality.

So, we can write:

18 (35) = Constant of proportionality

and

28 (x) = Constant of proportionality

From both these equation, we can write:

18 (35) = 28 (x)

⇒ x = 22.5

So, this means 28 electricians will do the same task in 22.5 days