Question

Mr. Kelso went shopping for school supplies. He purchased white boards for $0.79 each, sharpies for $1.56 each and glue sticks for $0.85 each and spent a total of $91.92. If he purchased five times the number of white boards as glue sticks and 10 more sharpies than glue sticks, how many of each item did he purchase?

Help please!

Answer 1

Let's call the number of white boards that Mr. Kelso purchased "W", the number of sharpies "S", and the number of glue sticks "G". We know the following information:

W = 5G

S = G + 10

And we also know the total cost of the items:

0.79W + 1.56S + 0.85G = 91.92

We can use the first equation to substitute for W in the second equation:

0.79(5G) + 1.56(G + 10) + 0.85G = 91.92

Expanding and simplifying the equation:

4.95G + 1.56G + 16.6 + 0.85G = 91.92

7.36G + 16.6 = 91.92

7.36G = 75.32

G = 10.25

So Mr. Kelso purchased 10 glue sticks. Using the first equation, we can find that he purchased 5 * 10.25 = 51 white boards. And using the second equation, we can find that he purchased 10.25 + 10 = 20.25 sharpies.

Since the number of each item must be a whole number, we round up or down to the nearest integer. In this case, it would make sense to round up the number of sharpies to 21. So Mr. Kelso purchased 51 white boards, 21 sharpies, and 10 glue sticks.