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A beginner artist kit costs $6.35 and contains 2 brushes and 5 jars of paint. The standard kit has 4 brushes and 12 jars of paint and cost $13.20. Assuming all brushes cost the same and all jars of paint cost the same, what are the prices of 1 brush and 1 jar of paint?

Respuesta :

2b + 5j = 6.35.....multiply by -2
4b + 12j = 13.20
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-4b - 10j = - 12.70 (result of multiplying by -2)
4b + 12j = 13.20
----------------------add
2j = 0.50
j = 0.50/2
j = 0.25 <==== jars

2b + 5j = 6.35
2b + 5(0.25) = 6.35
2b + 1.25 = 6.35
2b = 6.35 - 1.25
2b = 5.10
b = 5.10/2
b = 2.55 <=== brushes

so 1 brush (b) = 2.55 and 1 jar (j) = 0.25...total, if needed, = 2.80
1 brush = 2.55 and 1 jar = 0.25.