SOLUTION: Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have? I first tried to add .10(.25) and .05x (because I don'

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Question 176439This question is from textbook Teaching Textbooks
: Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have?
I first tried to add .10(.25) and .05x (because I don't know how many nickels, but that does not make sense when I try to solve it. I guess I don't understand what "10% as many" means. Does he have 10% more quarters? or 10% out of 100% are quarters? Either way, I can't figure out even how to set this problem up!
Thanks for your help! This question is from textbook Teaching Textbooks

Found 2 solutions by MathTherapy, checkley75:
Answer by MathTherapy(10552) (Show Source):
You can put this solution on YOUR website!
Irving has 10% as many quarters as nickels. If Irving has $5.25 in quarters and nickels, how many nickels does he have?
I first tried to add .10(.25) and .05x (because I don't know how many nickels, but that does not make sense when I try to solve it. I guess I don't understand what "10% as many" means. Does he have 10% more quarters? or 10% out of 100% are quarters? Either way, I can't figure out even how to set this problem up!
Thanks for your help!

10% as many quarters means that he has 10% less quarters than nickels. This means that if hypothetically he has 50 nickels, then he would have 5 (10% of 50)quarters.

Let amount of nickels = n
Then he has 10% of n = .1n in quarters
Since he has $5.25 in nickels and quarters, then we get:
.05(n) + .25(.1n) = 5.25
.05n + .025n = 5.25
.075n = 5.25
n = 5.25/.075
n = 70
He has 70 nickels

Answer by checkley75(3666) (Show Source):
You can put this solution on YOUR website!
.1x*.25+.05x=5.25
.025x+.05x=5.25
.075x=5.25
x=5.25/.075
x=70 number of nickels.
.1*70=7 number of quarters.
Proof:
7*.25+.05*70=5.25
1.75+3.50=5.25
5.25=5.25