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Mary has been saving her weekly allowance for the past 20 weeks. She started with $100 and now has $300. Which equation can be used to find the amount of money Mary receives for her weekly allowance?

User Eden
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1 Answer

3 votes

Answer:

Explanation:

You should set this up as an y = mx + b equation. Since 300 is her final number, that will be your y value. She started with 100, so that will be your b value. 20 is the number related to the variable you don't know so that will be your m.

300 = 20x + 100

-100 -100

200 = 20x

divide both sides by 20

10 = x

User Rafraf
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