Difference between revisions of "2007 AMC 10A Problems/Problem 5"
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− | Subtracting these equations yields <math>19n = 8.36 \Longrightarrow n = 0.44</math>. Solving backwards gives <math>p = 0.09</math>. Thus the answer is <math>16p + 10n = | + | Subtracting these equations yields <math>19n = 8.36 \Longrightarrow n = 0.44</math>. Solving backwards gives <math>p = 0.09</math>. Thus the answer is <math>16p + 10n = 5.84\ \mathrm{(B)}</math>. |
== See also == | == See also == |
Revision as of 12:10, 3 June 2021
Problem
The school store sells 7 pencils and 8 notebooks for . It also sells 5 pencils and 3 notebooks for
. How much do 16 pencils and 10 notebooks cost?
Solution
We let cost of one pencil in dollars,
cost of one notebook in dollars. Then
Subtracting these equations yields . Solving backwards gives
. Thus the answer is
.
See also
2007 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 4 |
Followed by Problem 6 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
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