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b = number of tickets sold before
a = number of tickets sold after
cost of a ticket = number of tickets times cost per ticket
before cost = 39.95b
after cost = 54.95a
total cost = 925000
39.95b + 54.95a = 925000
total number tickets = 20000
b + a = 20000
we have
39.95b + 54.95a = 925000
b + a = 20000
multiply second equation by -39.95 and add to first equation
39.95b + 54.95a = 925000
-39.95b-39.95a = -799000 +
0b+15a = 126000
15a = 126000
divide bot sides by 15
a = 8400
sub back
b + a = 20000
b+8400 = 20000
minus 8400 both sides
b = 11600
11,600 tickets sold before
8400 tickets sold after
Answer:
-26042
Step-by-step explanation:
sum of a finite geometric series =

here, a1 is the first term, r is the common ratio, and n is the number of terms
a1 = -2
r = -5
n = 7
