Answer:
28 nickels and 17 dimes
Step-by-step explanation:
A nickel is worth 5 cents and a dime is worth 10 cents
If there are X nickels and Y dimes
Total value = 5X + 10Y cents
$3.10 == 3.10 x 100 = 310 cents
So 5X + 10 Y = 310
Divide both sides by 5 to get
5X/5 + 10Y/5 = 310/5
X + 2Y = 62 (1)
The total number of coins is X + Y and is given to be 45
X + Y = 45 (2)
Subtract Eq(2) from Eq(1) to get
X + 2Y - (X + Y) = 62-45 = 17
X + 2Y - X - Y = 17
Collecting like terms
(X - X) + (2Y - Y) = 17
Y = 17
So number of dimes = 17
To find X, the number of nickels use equation (2)
X + 17 = 45
Subtract 17 from both sides
X + 17 - 17 = 45 - 17
X = 28
So number of nickels = 28