SOLUTION: The cost of 5 similar textbooks and 10 identical bookmarks is $63. 5 bookmarks cost as much as 2 textbooks. Find the cost of a textbook.

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Question 151275: The cost of 5 similar textbooks and 10 identical bookmarks is $63. 5 bookmarks cost as much as 2 textbooks. Find the cost of a textbook.
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!
Let "$x" = cost of bookmark; "$y" = cost of textbook
There 5 bookmarks & 10 textbooks that cost $63. Equating that fact,
5x%2B10y=63 -------------------> eqn 1
Also, 5 bookmarks cost as much as 2 textbooks. Equating that fact,
5x=2y -------------------------> eqn 2
In eqn 2 we get, x=%282y%29%2F5 and substitute in eqn 1,
cross%285%29%28%282y%29%2Fcross%285%29%29%2B10y=63
12y=63 ---------------> y=63%2F12 ------> y=$5.25/each for textbook
To finish it, go back eqn 2,
5x=2%285.25%29 ---------->x=10.5%2F5 -------> x=$2.10/each for bookmark
In doubt? go back eqn1,
5%282.10%29%2B10%285.25%29=63
10.5%2B52.5=63
63=63, cool!
Thank you
Jojo