Answer:
7/√2 cm
Step-by-step explanation:
Area of circle = 77 cm^2
=> π(r)^2 = 77
=> (22/7) x (r)^2 = 77
=> (r)^2 = (77 x 7) / 22
=> (r)^2 = 49/2
=> (r) = 7/√2 cm
<h3>
Answer: Choice B</h3>
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Explanation:
The rule we use is
![\Large a^{m/n} = \sqrt[n]{a^m} = \left(\sqrt[n]{a}\right)^m](https://tex.z-dn.net/?f=%5CLarge%20a%5E%7Bm%2Fn%7D%20%3D%20%5Csqrt%5Bn%5D%7Ba%5Em%7D%20%3D%20%5Cleft%28%5Csqrt%5Bn%5D%7Ba%7D%5Cright%29%5Em)
where 'a' is the base, m stays in the role of the exponent, and n plays the role of the root index (eg: n = 3 is a cube root, n = 4 is a fourth root, and so on).
So for instance,
![\Large 2^{3/4} = \sqrt[4]{2^3} = \left(\sqrt[4]{2}\right)^3](https://tex.z-dn.net/?f=%5CLarge%202%5E%7B3%2F4%7D%20%3D%20%5Csqrt%5B4%5D%7B2%5E3%7D%20%3D%20%5Cleft%28%5Csqrt%5B4%5D%7B2%7D%5Cright%29%5E3)
or in this case,
![\Large t^{5/8} = \sqrt[8]{t^5} = \left(\sqrt[8]{t}\right)^5](https://tex.z-dn.net/?f=%5CLarge%20t%5E%7B5%2F8%7D%20%3D%20%5Csqrt%5B8%5D%7Bt%5E5%7D%20%3D%20%5Cleft%28%5Csqrt%5B8%5D%7Bt%7D%5Cright%29%5E5)
Answer : 0.0129
Step-by-step explanation:
Given : Based on FAA estimates the average age of the fleets of the 10 largest U.S. commercial passenger carriers is
years and standard deviation is
years.
Sample size : 
Let X be the random variable that represents the age of fleets.
We assume that the ages of the fleets of the 10 largest U.S. commercial passenger carriers are normally distributed.
For z-score,

For x=14

By using the standard normal distribution table , the probability that the average age of these 40 airplanes is at least 14 years old will be :-

Hence, the required probability = 0.0129
Answer:
7m
Step-by-step explanation:
18/6 = 3
24/8 = 3
21/x = 3
21/3 = 7
x = 7