A college received 90% of its order of laptop keyboards from a vendor. Some of the keyboards were defective. The equation below represents this

situation, where x represents the total number of keyboards ordered and y

represents the number of keyboards that were non-defective. y = 0.9x -

1/18(0.9x) If the college ordered 200 keyboards, how many non-defective

keyboards did the college receive?*

170

Step-by-step explanation:

Given that: x represents total number of keyboards ordered

                  y represents number of non-defective keyboards

And;

                  y = 0.9x -    .......................... 1

If the college ordered 200 keyboards, then x = 200. So that substituting the value of x in equation 1, we have;

y = (0.9 x 200) -

  = 180 -

  = 180 - 10

y = 170

The college received 170 non-defective keyboards.