Answer:
Step-by-step explanation:
1) Number of nickels = x
Number of quarter = y
x + y = 7 ----------------------(I)
x = 7 - y ------------------------(II)
0.05x + 0.25y = 0.55 -----------(III)
Substitute s = 7 - y in equation (III)
0.05*(7 - y) + 0.25y = 0.55
0.05*7 - 0.05*y + 0.25y = 0.55
0.35 - 0.05y + 0.25y = 0.55 {Combine like terms}
0.35 + 0.20y = 0.55 {Subtract 0.35 from both sides}
0.2y = 0.55 - 0.35
0.2y = 0.2 {Divide both sides by 0.2}
y = 0.2/0.2
y = 1
Substitute y =1 in equation (II)
x = 7 - 1
x = 6
Number of nickels = 6
Number of quarter = 1
2) Number of children tickets = x
Number of adult tickets = y
x + y = 40 -----------------(I)
x = 40 - y -----------------(II)
2x + 5y = 170 -----------------(III)
Substitute x = 40 - y in equation (III)
2*(40-y) + 5y = 170
2*40 - 2*y + 5y = 170
80 - 2y + 5y = 170 {Combine like terms}
80 + 3y = 170 {Subtract 80 from both sides}
3y = 170 - 80
3y = 90 {Divide both sides by 3}
y = 90/3
y = 30
Substitute y = 30 in equation (II)
x = 40 - 30
x = 10
Number of children tickets = 10
Number of adult tickets =30
