A + c = 824 represents number of tickets to sell
20a + 12c = 13,344 represents cost of each type of ticket
multiply equation 1 by -12 to cancel the variable 'c' and solve for 'a'
-12(a + c = 824)
-12a - 12c = - 9888
20a + 12c = 13,344 add equations together
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8a = 3456 divide both sides by 8
a = 432
To find children's tickets substitute adult numbers back into equation 1.
a + c = 824
432 + c = 824
subtract 432 from both sides
c = 392
adult 432, children 392
Answer:
25 cent stamps = 13 and 29 cent stamps = 15
Step-by-step explanation:
x = 25 cent stamps and y = 29 cent stamps
x + y = 28......x = 28 - y
0.25x + 0.29y = 7.60
0.25(28 - y) + 0.29y = 7.60
7 - 0.25y + 0.29y = 7.60
-0.25y + 0.29y = 7.60 - 7
0.04y = 0.60
y = 0.60 / 0.04
y = 15 <===== 29 cent stamps
x + y = 28
x + 15 = 28
x = 28 - 15
x = 13 <===== 25 cent stamps
lets check it...
0.25x + 0.29y = 7.60
0.25(13) + 0.29(15) = 7.60
3.25 + 4.35 = 7.60
7.60 = 7.60 (correct..it checks out)
5(x-3)-x =
Multiply Everything In The Parentheses By 5
5x-15-x