SOLUTION: I am so confused by this. My mom tried to help me but she doesn't understand either. There is one of the questions I am supposed to solve. If someone can show me the steps to th

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Question 170598: I am so confused by this. My mom tried to help me but she doesn't understand either. There is one of the questions I am supposed to solve. If someone can show me the steps to this one maybe I can figure out the others.
Maria has $7.30 in dimes and quarters. She has 34 coins. How many dimes could she possibly have? Explain your answer. Don't forget to show your work!
(Hint: The problem could be solved using a linear system of equations. Try to set up an equation indicating the number of coins and another equation with their value.)

Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website!
ok lets call the number of dimes and quarters d and q respectively.
:
dimes are worth 10cents and quarters are 25 cents so if you take the number of dimes(d) and multiply it by 10cents and the number of quarters (q) and multiply it by 25 cents then it will equal $7.30 right!!!!
:
.10d+.25q=7.30....eq 1.......and we know that the total number of coins(dimes and quarters) (d and q)=34
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d+q=34....eq 2--->d=34-q
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now we have two unknowns and two equations....take d's value from eq 2 and plug it into eq 1
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.10(34-q)+.25q=7.3--->distribute
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3.4-.1q+.25q=7.3---->combine like terms
:
.15q=3.90
:quarters
dimes