Let:
x = cost of senior citizen ticket
y = cost of student ticket
4x + 5y = 102
7x + 5y = 126
4x + 5y = 102
4x = 102 - 5y
x = (102 - 5y)/4
x = 102/4 - 5y/4
7x + 5y = 126
7(102/4 - 5y/4) + 5y = 126
(714/4 - 35y/4) + 5y = 126
-35y/4 + 5y = 126 - 714/4
note:
-35y/4 = -8.75y
714/4 = 178.5
-8.75y + 5y = 126 - 178.5
-3.75y = -52.5
y = -52.5/-3.75
y = 14
x = 102/4 - 5y/4
x = 102/4 - 5(14)/4
x = 8
x = cost of senior citizen ticket = $8/ea
y = cost of student ticket = $14/ea
Answer:
x = 2
Step-by-step explanation:
Taking antilogs, you have ...
2³ × 8 = (4x)²
64 = 16x²
x = √(64/16) = √4
x = 2 . . . . . . . . (the negative square root is not a solution)
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You can also work more directly with the logs, if you like.
3·ln(2) +ln(2³) = 2ln(2²x) . . . . . . . . . . . write 4 and 8 as powers of 2
3·ln(2) +3·ln(2) = 2(2·ln(2) +ln(x)) . . . . use rules of logs to move exponents
6·ln(2) = 4·ln(2) +2·ln(x) . . . . . . . . . . . . simplify
2·ln(2) = 2·ln(x) . . . . . . . . . . . subtract 4ln(2)
ln(2) = ln(x) . . . . . . . . . . . . . . divide by 2
2 = x . . . . . . . . . . . . . . . . . . . take the antilogs
Below are the solutions:
A)
Ohio: 8.23 * 10^5
US: 3.19 * 10^8
B)
(3.19 * 10^8)/(8.23 * 10^5) = 3.19/8.23 * 10^8/10^5
= 3.19/8.23 * 10^3 = 0.387606318 * 10^3
= 387.606318
The population of US is 387 times larger than that of Ohio's
