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Im stuck on this question

Im stuck on this question-example-1

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w = amount of wagon stamps

b = amount of sailboat stamps

so hmm we know Megan bought 4 stamps, so whatever "w" and "b" are, we know that w + b = 4.

we also know that Megan spent 16 cents on all, and that the wagon ones cost 1c, so for "w" amount that's a total of 1*w or 1w. Now, the sailboat stamps cost 5c, that will give us a total of 5*b or 5b for those.


w+b=4\implies b=4-w \\\\[-0.35em] ~\dotfill\\\\ 1w+5b=16\implies \stackrel{\textit{substituting from the 1st equation}}{1w+5(4-w)=16} \implies w+20-5w=16 \\\\\\ 20-4w=16\implies 20=4w+16\implies 4=4w\implies \cfrac{4}{4}=w\implies \boxed{1=w} \\\\\\ \stackrel{\textit{since we know that}}{b=4-w}\implies b=4-1\implies \boxed{b=3}

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