C=2pir
A=pir^2
45=pir^2
divide both sides by pi (aprox pi=3.141592)
14.32394785=r^2
sqrt both sides
3.784699176=r
sub
C=2pir
C=(2)(pi)(3.784699176)
aprox pi=3.141592
C=23.779961311m
Answer: After 8 hours the pressure will be at -60?
Explanation: not sure how the balloon can reach -60 kilopascals but 15% of 300 is 45 and 45 x 8(hours) is 360. 300 - 360 is -60
<span>x + y = 56
x = 4y
---
4y + y = 56
5y = 56
y = 10.4
x = 41.6</span>
I'm assuming that x is part of the data set, and, with x, the mean equals 105. To find the value of x, you must add all the data values together to get 544+x (you still don't know what x equals). Then put 544+x over how many days values there are, including x (there are 6). You should have 544+x/6. Now, as this is how you would calculate the mean if you knew what x was equal to, you must set it equal to the mean, since you know what it is (105). You should now have 544+x/6 = 105. You have your equation set up--now you just have to solve it. I would multiply by 6 on both sides to get rid of the 6 on the left side. You would then have 544+x = 630. I would finally subtract 544 from both sides to get x = 86. Your final answer is x = 86.
