Answer: Choice B
500 = 400 + 50s. Therefore, Bart can buy 2 pairs of shoes.
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Explanation:
s = number of pairs of shoes
50s = amount spent on shoes ($50 per pair)
50s+400 = total amount spent on shoes and uniforms
That expression is the same as 400+50s because we can add numbers in any order we want. Set this equal to the $500 he started with to get the equation 500 = 400 + 50s
We have enough info to determine the answer must be choice B
We can stop here if you wanted.
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Let's solve that equation for s
500 = 400 + 50s
400 + 50s = 500
50s = 500-400 .... subtract 400 from both sides
50s = 100
s = 100/50 .... divide both sides by 50
s = 2
This means he can buy 2 pairs of shoes.
Buying the shoes only will cost 50s = 50*2 = 100 dollars, which on top of the $400 for the uniforms, leads to a grand total of 400+50s = 400+100 = 500 dollars. This helps confirm we have the correct value for s.
