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Orlov [11]
3 years ago
9

Sarah bought pencils and markers for school. She bought 3 times as many pencils as markers.

Mathematics
1 answer:
Serhud [2]3 years ago
7 0

Answer:

Sarah bought 30 pencils

Step-by-step explanation:

1. Let define p, as the number of pencils bought, and m, as the number of markers bought.

2.

0.15p+0.30m=7.50

p=3m

3. Substitute p in the first equation to 3m since p=3m as defined.

0.15(3m) + 0.30m=7.50\\0.45m+0.30m=7.50\\0.75m=7.50\\m=10

plug m into equation p=3m to find the number of pencils bought

p=3m=3(10)=30

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