Noelle has 39 coins in her pocket, all of which are nickels and quarters.

Question

Noelle has 39 coins in her pocket, all of which are nickels and quarters. If the total value of her change is $5.35, how many nickels and how many quarters does she have?

Number of nickels that Noelle has = 

Number of quarters that Noelle has 

Answer 1

From Jon's answer

N + Q = 39

N*0.05 + Q*0.25 = 5.35

multiply fist equation by -.05

-0.05N - 0.05Q= -1.95

0.05N+0.25Q =5.35

add equations

0.2Q=3.4

Q=17

N +17 = 39

N= 39-17 =22

Answer 2

N = number of nickels

Q = number of quarters

N + Q = 39

N*0.05 = value of nickels

Q * 0.25 = value of quarters

N*0.05 + Q * 0.25 = 5.35 total value

we have two equations in two unknowns:

N + Q = 39

N*0.05 + Q*0.25 = 5.35

Solve for either N or Q in 1st equation and plug into second equation to get one variable value then plug that value back into the first equation to get the second variable value.