If my usage increases a utility bill by an average of 72% what percentage of the total bill should I pay each month?

Question

I think the question is clear.

Answer 1

Question is not clear to me,

But I am assuming 72% increase is for a year.

Let total bill be x. then the 72% increase would result in x + 0.72x = 1.72x

So you will have to pay 1.72x/12 or 0.143333x per month.

So, the percent of the bill you have to pay per month = 0.143333x/1.72x = 0.0833 or 8.333%

Answer 2

Your monthly rate will also increase by 72%.

For example, if your utility bill for the year is $168 and it increases by 72% to $288.96, and you were paying $14 a month, this will rise to $24.08, which is a 72% rise in the monthly payment.

Note that this assumes that there is no additional charge for paying the bill monthly rather than annually. The percentage of the utility bill you pay each month does not depend on the percentage increase in the utility charge: it’s always going to be a twelfth (8.3%) of the annual charge. Some utility companies discount the one-off annual payment, so that monthly payments are higher than one twelfth of the annual charge. But there is no more information in the question about this, so the assumption stands.