Bill has 30 coins, some nickels some dimes. They equal $2.10. How many nickels are there? What is the equasion used to solve this problem? When I solve it, I get 4.3 nickels, but how can there be .3? Please help me solve

I posted the two equations for this about an hour ago. Show your work and I'll find your error.

N + D = 30
5N + 10D = 210
Multiply the first by 5 and subtract from the second and you will have your answers.

To solve this problem, we can set up a system of equations. Let's use N to represent the number of nickels and D to represent the number of dimes.

First, we have the equation N + D = 30, because the total number of coins is 30.

Next, we have the equation 5N + 10D = 210, representing the total value of the coins, which is $2.10 in cents.

To solve the system of equations, we can follow these steps:

1. Rearrange the first equation to get N = 30 - D.
2. Substitute this expression for N into the second equation: 5(30 - D) + 10D = 210.
3. Distribute the 5 to the terms inside the parentheses: 150 - 5D + 10D = 210.
4. Simplify the equation: 150 + 5D = 210.
5. Subtract 150 from both sides: 5D = 60.
6. Divide both sides by 5 to solve for D: D = 12.

Now, we have found that the number of dimes, D, is equal to 12. To find the number of nickels, N, we can substitute this value back into either of the original equations.

Using N + D = 30, we have: N + 12 = 30.
Subtracting 12 from both sides, we find that N = 18.

Therefore, there are 18 nickels and 12 dimes.

Regarding the decimal part, it seems that you made an error in your calculation. The solution does not involve a fractional or decimal value, as the problem only involves whole coins (nickels and dimes). The equation method used here should lead to whole-number solutions.

n=5

d=28