An Office supply store sells spiral notebook paper for $2.50 each and notebook paper made of recycled paper of?


office supply
….. asked:


$2.30. At the start of the spring semester, a combination of 50 of these types of paper was sold for a total of $118.60. How many of each type of paper was sold?

anybody know??

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2 Responses to “An Office supply store sells spiral notebook paper for $2.50 each and notebook paper made of recycled paper of?”

  1. Lucy Says:
    February 13th, 2009 at 1:36 pm

    HINT: Write what you know in a table.

    Variables:
    s = # of spiral notebook paper sold
    r = # of recycled notebook paper sold

    Given: spiral notebook paper for $2.50 each
    Means: 2.5 * s = 2.5s = value of spiral notebook paper sold

    Given: notebook paper made of recycled paper for $2.30
    Means: 2.3 * r = 2.3r = value of recycled notebook paper sold

    Given: 50 of these types of paper
    Means: s + r = 50

    Given: sold for a total of $118.60
    Means: 2.5s + 2.3r = 118.6

    You have 2 equations:
    s + r = 50
    2.5s + 2.3r = 118.6

    Solve the first one for s.
    s + r = 50
    s = 50 - r

    Plug this into the second equation.
    2.5s + 2.3r = 118.6
    2.5(50 - r) + 2.3r = 118.6
    125 - 2.5r + 2.3r = 118.6
    125 - 118.6 = 2.5r - 2.3r
    125 - 118.6 = 2.5r - 2.3r
    6.4 = 0.2r
    6.4 / 0.2 = r
    r = 32

    Plug this solved r value into s = 50 - r to solve for s.
    s = 50 - r
    s = 50 - 32
    s = 18

    ANSWER: 18 of the spiral notebook paper and 32 of the recycled notebook paper were sold.

  2. Dr. Nightcall Says:
    February 16th, 2009 at 7:47 am

    Let s = spiral and r = recycled
    s+r= 50
    2.5s + 2.3r = 118.60
    Solve the first equation for either variable. I chose s.
    s = 50 - r
    Now substitute into the second.

    2.5(50-r) + 2.3r = 118.6
    125 - 2.5r + 2.3 = 118.6
    -.2r = -6.4
    r = 32 s = 18
    So 32 recycled and 18 spiral. Substitute these into the second equation to check our work.

    2.5(18) + 2.3(32) = 118.60
    45 + 73.6 = 118.60
    118.60 = 118.60

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