2.4k views
3 votes
Thirty coins, all dimes and nickels, are worth $2.60. How many nickels are there. Create two equations and solve.

2 Answers

4 votes

Final answer:

To solve the problem, set up two equations representing the given information: x + y = 30 for the total number of coins and 5x + 10y = 260 for the total value of the coins. Solve the system of equations using substitution or elimination method to find the number of nickels and dimes.

Step-by-step explanation:

To solve this problem, we can set up two equations to represent the given information.

Let x be the number of nickels and y be the number of dimes.

From the problem, we know that:

  1. The total number of coins is 30: x + y = 30
  2. The total value of the coins is $2.60: 5x + 10y = 260 (since a nickel is worth 5 cents and a dime is worth 10 cents)

We now have a system of two equations. We can solve this system by either substitution or elimination method.

Substitution Method:

  1. Solve one equation for one variable (e.g., x = 30 - y)
  2. Substitute this expression into the other equation
  3. Solve the resulting equation for the other variable (e.g., 5(30 - y) + 10y = 260)
  4. Solve for y, and then substitute the obtained value of y into one of the original equations to solve for x.

Elimination Method:

  1. Multiply one equation by a constant so that the coefficients of one variable are the same in both equations
  2. Add or subtract the equations to eliminate one variable
  3. Solve the resulting equation for the remaining variable
  4. Substitute this value into one of the original equations to solve for the other variable.

By solving the system of equations, we can determine the number of nickels and dimes.

User Catskul
by
5.6k points
4 votes

Answer:8 nickels



Step-by-step explanation:

10x22=220

5x8=40

220+40=260

User Domsom
by
5.9k points