Answers:
Expression for the total number of quarters is 40*1.20
Amount of money you have left is 6 dollars
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Step-by-step explanation:
You start with 40 quarters. 20% of this is 0.20*40 = 8 which means you found 8 more quarters. The total goes from 40 to 40+8 = 48.
A slight shortcut is to write 40*1.20 = 48
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48 quarters = 48*0.25 = 12 dollars
Or you can divide by 4 to determine the total value of the quarters in dollars.
If you spent half (50%) of that money, then you'll be left with 6 dollars.