Question

There are 142 coins in a piggy bank with a total value of $20.50. If all the coins are either quarters or nickels, which system would you use to determine how many of each type of coin are in the piggy bank?

Answer 1

Number of quarters = 67

Number of nickels = 75

Explanation:

Please kindly check the attached files for explanation.

Answer 2

Quarters = 67

Nickel = 75

Explanation:

Using simultaneous equations.

Let x represent the number of quarters and y the number of nickel.

1 quarter = $0.25

1 nickel = $0.05

Given;

Total number of coin = 142

So,

x + y = 142 ....1

Total value = $20.50

0.25x + 0.05y = 20.50 ......2

Divide equation 2 by 0.25;

x + 0.20y = 82 .....3

Subtract equation 3 from 1

y - 0.20y = 142-82

0.80y = 60

y = 60/0.80

y = 75

from equation 1

x+y = 142

x = 142-y = 142-75

x = 67

Number of each coin.

Quarters = 67

Nickel = 75