Answer:
x = number of quarters = 25
y = number of dimes = 15
Step-by-step explanation:
Let
x = number of quarters
y = number of dimes
1 dime = $0.10
1 quarter = $0.25
x + y = 40 (1)
0.25x + 0.10y = 7.75 (2)
From (1)
x = 40 - y
Substitute x = 40 - y into (2)
0.25x + 0.10y = 7.75 (2)
0.25(40 - y) + 0.10y = 7.75
10 - 0.25y + 0.10y = 7.75
- 0.25y + 0.10y = 7.75 - 10
-0.15y = -2.25
y = -2.25/-0.15
y = 15
Substitute y = 15 into (1)
x + y = 40 (1)
x + 15 = 40
x = 40 - 15
x = 25
x = number of quarters = 25
y = number of dimes = 15
Total quarters = 25 × $0.25
= $6.25
Total dimes = 15 × $0.10
= $1.5
