Question 71801
x + y = 250
I think the $amt equation should be
.05x + .10y = 21.25
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In my problem x= nickels and y=dimes, how many dimes and how many nickels do I have?
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Take the the 1st equation (total number of coins):
x + y = 250
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Subtract y from both sides:
x = (250 - y)
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Substitute (250-y) for x in the 2nd equation ($$ amount)
.05x + .10y = 21.25
.05(250-y) + .10y = 21.25
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Mult what is inside the brackets:
12.50 - .05y + .10y = 21.25
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Subtract 12.50 from both sides:
-.05y + .10y = 21.25 - 12.50
+.05y = 8.75
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Divide both sides by .05 and you have the value of y (dimes)
y = 8.75/.05
y = 175 dimes:
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Substitute 175 for y in the 1st equation to find the number of nickels;
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Check your solutions by substituting for both x and y in the 2nd equation to
confirm equality