Respuesta :
0.05x + 0.10(35-x) = 2.50
Get rid of decimals by multiplying every term by 100:
5x + 10(35-x) = 250
5x + 350 - 10x = 250
-5x + 350 = 250
-5x = -100
x = 20 = the number of nickels.
The number of dimes is 35-x or 35-20 or 15 dimes.
Checking: 20 nickels is $1.00 and 15 dimes is $1.50
And indeed $1.00 + $1.50 = $2.50
Edwin
By solving a system of equations we will see that Sandy has 20 nickels and 15 dimes.
How to solve a system of equations?
We need to define the variables:
- x = number of dimes
- y = number of nickels.
We know that there are 35 coins so:
x + y = 35
And the total values if $2.50, then:
x*$0.10 + y*$0.05 = $2.50
Then our system is:
x + y = 35
x*$0.10 + y*$0.05 = $2.50
To solve this, we need to isolate one of the variables in one of the equations. I will isolate x on the first equation:
x = 35 - y
Now we replace this on the other equation:
(35 - y)*$0.10 + y*$0.05 = $2.50
$3.5 - y*$0.05 = $2.50
$3.50 - $2.50 = y*$0.05
$1.00/$0.05 = y = 20
So there are 20 nickels and the other 15 coins are dimes.
If you want to learn more about systems of equations, you can read:
https://brainly.com/question/13729904