Question 761416: Kate has 21 coins (nickels and dimes) in her purse. How many nickels and dimes does she have if she has $1.50? Found 2 solutions by Cromlix, Alan3354:Answer by Cromlix(4381) (Show Source):
You can put this solution on YOUR website! Nickels = x
Dimes = y
x + y = 21...1
5x + 10y = 150...2
Multiply (1) by 10
10x + 10y = 210...3
5x + 10y = 150...2
Subtract (2) from (3)
5x = 60
x = 12
Substitute x = 12 into Eq(1)
x + y = 21
12 + y = 21
y = 21 - 12
y = 9
So, Kate has 12 nickels and 9 dimes
Hope this helps.
:-)
You can put this solution on YOUR website! Kate has 21 coins (nickels and dimes) in her purse. How many nickels and dimes does she have if she has $1.50?
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Another approach:
If she had 21 dimes it would be $2.10
Each dime replaced by a nickel reduces the amount by 5 cents.
210 - 150 = 60
60/5 = 12 nickels
--> 9 dimes
