Inverse Variation Question 1 with Solutions

Last week, I went over inverse variation, and I gave you four inverse variation problems to try on your own. You can see that post here: Inverse Variation

Today I would like to give a solution to the first of those four problems. I will give solutions to the other three problems throughout this week.

Example: If y = k/x and y = 9 when x = 14, then what is y when x = 6 ?

Try to solve the problem yourself before checking the solutions below.

Solutions: 

(1) We are given that y = 9 when x = 14, so that 9 = k/14, or k = 126. Thus, y = 126/x. When x = 6, we have y = 126/6 = 21.

(2) Since y varies directly as x,  xy  is a constant. So, we get the following equation:  (14)(9) = 6y. So, 126 = 6y, and y = 126/6 = 21.

(3) (14)(9)/6 = 21.

More Problems with Explanations

If you are preparing for the SAT, ACT, or an SAT math subject test, you may want to take a look at the Get 800 collection of test prep books.

And if you liked this article, please share it with your Facebook friends:

Comments

comments