195k views
3 votes
Julio has $2.75 in his pocket in nickels and dimes. The number of dimes is 10 less than twice the number of nickels. Find the number of each type of coin.

1 Answer

4 votes

Answer: Dimes= 20, Nickels= 15

Explanation:

Since we are looking for the amount of coins, we can use system of equations to solve for the amount of coins.

Equation 1:

0.1x+0.05y=2.75

This equation comes from the total cost. x stands for dimes and y stands for nickels. 0.1 is the worth of a dime and 0.05 is the worth of a nickel.

Equation 2:

x=2y-10

This equation comes from 10 less than twice the number of nickels.

We can use substitution to find x and y.

0.1(2y-10)+0.05y=2.75

0.2y-1+0.05y=2.75

0.25y-1=2.75

0.25y=3.75

y=15

There are 15 nickels.

Now that we have y, we can plug it back into the equation to find x.

x=2(15)-10

x=30-10

x=20

There are 20 dimes.

User Goran
by
8.2k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories