Answer:
B = 31, C = 11
Step-by-step 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 .