Question 943617
A local Computer City sells batteries ($4) and small boxes of pens ($7). In August, total sales were $1,995. Customers bought 7 times as many batteries as boxes of pens.

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Equations:
Quantity Eq:: b = 7p
Value Eq::: 4b + 7p = 1995
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Substitute for "b" and solve for "p"::
4(7p) + 7p = 1995
35p = 1995
p = 57 (# of boxes of pens sold)
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Solve for "b"::
b = 7p
b = 399 (# of batteries sold)
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Cheers,
Stan H.
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