SOLUTION: Austin has enough money to buy either 90 granola bars or 78 pop tarts. After returning from the store, Austin has no money, 75 granola bars, and X amount of pop tarts. Assuming tha

Algebra ->  Exponents -> SOLUTION: Austin has enough money to buy either 90 granola bars or 78 pop tarts. After returning from the store, Austin has no money, 75 granola bars, and X amount of pop tarts. Assuming tha      Log On


   



Question 1108160: Austin has enough money to buy either 90 granola bars or 78 pop tarts. After returning from the store, Austin has no money, 75 granola bars, and X amount of pop tarts. Assuming that Austin has not eaten anything, figure out what X is.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I will say that he had $100 to spend
That means each granola bar costs +100%2F90+ dollars
and each pop tart costs +100%2F78+ dollars
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I can say:
+%28+100%2F90+%29%2A75+%2B+%28+100%2F78+%29%2A+x+=+100+
Divide both sides by +100+
+75%2F90+%2B+x%2F78+=+1+
+x%2F78+=+90%2F90+-+75%2F90+
+x%2F78+=+15%2F90+
+x%2F78+=+1%2F6+
+x+=+78%2F6+
+x+=+13+
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check:
+75%2F90+%2B+13%2F78+=+1+
+5%2F6+%2B+1%2F6+=+1+
OK