A student buys 5-cent, 10-cent, and 15-cent stamps, with a total value of $6.70. If the number of 5-cent stamps is 2 more than the num

Question

A student buys 5-cent, 10-cent, and 15-cent stamps, with a total value of $6.70. If the
number of 5-cent stamps is 2 more than the number of 10-cent stamps, while the
number of 15-cent stamps is 5 more than one half the number of 10-cent stamps, how
many 15-cent stamps did the student obtain?

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Delwyn 1 day 2021-07-21T05:09:47+00:00 1 Answers 0 views 0

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    2021-07-21T05:11:41+00:00

    The value of the 10 cent stamps is, as you said, , the value of the 5 cent stamps is and the value of the 15 cent stamps is 15(0.5n + 5). These three values add up to the total value of the stamps, namely $6.70.

    10n + 5(n+2) + 15 (1/2n + 5) = 6.70

    10n +5n + 10 + 15/2n + 75 =670

    10n + 5n + 15/2n =585

    20n + 10n + 15n = 1170

    45n = 1170

    N=26

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