SOLUTION: I have 14 coins equaling $2.10. I only have quarters and nickels. How many do j have of each?

Question 961167: I have 14 coins equaling $2.10. I only have quarters and nickels. How many do j have of each?
Answer by macston(5194) (Show Source): You can put this solution on YOUR website!
Q=quarters; N=nickels
Q+N=14
Q=14-N Use this to substitute for Q
$0.25Q+$0.05N=$2.10 This converts number of quarters and nickels to dollars.
$0.25(14-N)+$0.05N=$2.10 This substitutes for Q (from above) to leave one variable.
$3.50-$0.25N+$0.05N=$2.10 Subtract #3.50 from each side.
-$0.20N=-$1.40 Divide each side by -$0.20
N=7 ANSWER 1:There are 7 nickels
Q=14-N=14-7=7 ANSWER 2: There are 7 quarters.
CHECK:
$0.25Q+$0.05N=$2.10
$0.25(7)+$0.05(7)=$2.10
$1.75+$0.35=$2.10
$2.10=$2.10
RELATED QUESTIONS
if i have a pocket composed of 2.50 and i only have quarters and nickels i have 14 coins... (answered by stanbon)

If I have only quarters and nickels and I have 75 coins totaling $7.35. How many of each... (answered by fractalier)

I have 25 coins in my pocket, only quarters and nickels and all together they equal... (answered by stanbon)

If I have a dollar ninety five made of quarters and nickels and only have 15 coins how... (answered by josgarithmetic)

I have $6.40. I have 2 more quarters than dimes, but 4 times as many nickels as quarters. (answered by ewatrrr)

My piggy bank has 28 coins in it that are only nickels, dimes, and quarters. I have... (answered by Alan3354,ikleyn)

I have 14 coins, dimes and nickels, for a total of $1.00. How many of each do I... (answered by Edwin McCravy)

I have 3 more quarters than dimes, and 2 less nickels than dimes for a total of $3.45.... (answered by CubeyThePenguin)

I have 21 coins in my wallet, all nickels and quarters. The total value of the coins is... (answered by Cromlix)