Question

An office supply store recently sold a black printer ink cartridge for $14.99 and a color printer ink cartridge for $20.99. At start of a recent fall semester, a total of 42 of these cartidges was sold for a total of $695.58. How many of each type were purchased?

Answer 1

B = 31, C = 11

Explanation:

Let B be the number of Black printer ink cartridges and C be the number of color printer ink cartridges.

42 were sold in total, hence,

B+C= 42 ------------(1)

Also, its given that

14.99 B+20.99C= 695.58 ------(2)

Multiplying (1) by 20.99,

14.99 B+14.99 C= 629.58 ------(3)

Now, subtracting (3) from (2),

14.99 B+20.99C= 695.58

14.99 B+14.99 C= 629.58

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6 C = 66

C= 66/6

C = 11

We know, B+ C= 49

Hence B = 42- 11 = 31

B = 31

Hence, number of Black printer ink cartridges = 31 and color printer ink cartridges = 11 .