<span>To find the circumference, the area first needs to be found to discover the radius. Area equals (r^2) multiplied by pi, or approximately 3.14. In this case, 12.5/3.14 gives a radius^2 of 3.98 feet. The square root of 3.98 is 1.99 feet. Using the radius, the diameter and circumference can now be found. The diameter is (2r), which would also be 3.98 feet in this case. 3.98 * 3.14 gives a circumference of 12.4972 feet.</span>
Answer:
Step-by-step explanation:
Letting "a" and "c" represent the costs of adult tickets and child tickets, the problem statement gives us two relations:
3a +5c = 52
2a +4c = 38
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We can solve this system of equations using "elimination" as follows:
Dividing the first equation by 2 we get
a +2c = 19
Multiplying this by 3 and subtracting the first equation eliminates the "a" variable and tells us the price of a child ticket:
3(a +2c) -(3a +4c) = 3(19) -(52)
c = 5 . . . . . . collect terms
a +2·5 = 19 . . substitute for c in the 3rd equation above
a = 9 . . . . . . subtract 10
One adult ticket costs $9; one child ticket costs $5.
