Answer:
300 nickels
Step-by-step explanation:
Reading the question, someone has 435 nickels and dimes.
The total is $28.50.
You're trying to find how many nickels he has.
All you need to do is set up a system of equations.
I'm going to use x as the number of nickels and y as the number of dimes.
Based on the question, you can say that
x + y = 435
(the number of nickels and dimes have t equal 435)
and 0.05x + 0.1y = $28.50
(nickels are 5 cents and dimes are 10 cents)
You want to solve for x, the number of nickels.
You can manipulate the first equation by subtracting x on both sides.
After you do that, you will get y = 435 - x. Now, you can substitute this equation into the second one.
First, you can distribute the 0.1.
0.05x + 0.1(435 - x) = 28.50
Then, you can put the two x's together.
0.05x + 43.5 -0.1x = 28.50
Next, you can subtract 43.5 on both sides to isolate x.
-0.05x + 43.5 = 28.50
Finally, you can divide on both sides to get x, which is the number of nickels.
-0.05x = - 15
x = 300 nickels
