Answer: 1
Step-by-step explanation:
If a random variable x is uniformly distributed in [a,b] the
Mean = 
Standard deviation : 
Let x = Times required for a cable company to fix cable problems
As per given.
x is uniformly distributed between 40 minutes and 65 minutes.
Then , mean =
minutes
Standard deviation :
minutes
Consider , P (mean- 2(Standard deviation) < X < mean+2(Standard deviation) )
= P(52.5-2(7.22)< X < 52.5+2(7.22))
=P(38.06 <X < 66.94 ).
But x lies between 40 minutes and 65 minutes.
Also, [40 minutes, 65 minutes]⊂ [38.06 minutes , 66.94 minutes]
Therefore ,P(38.06 <X < 66.94 ) =1
∴ The probability that a randomly selected cable repair visit falls within 2 standard deviations of the mean is 1.
Answer:
a = 2, b = 3.5
Step-by-step explanation:
Expanding
using Binomial expansion, we have that:
=


We have that the coefficients of the first two terms are 128 and -224.
For the first term:
=>
=> ![a = \sqrt[7]{128}\\ \\\\a = 2](https://tex.z-dn.net/?f=a%20%3D%20%5Csqrt%5B7%5D%7B128%7D%5C%5C%20%5C%5C%5C%5Ca%20%3D%202)
For the second term:

Therefore, a = 2, b = 3.5
Answer: 1439
Step-by-step explanation:
Volume= Length* breadth* height
= 15*1312*112
= 1439
Answer:
the first one
Step-by-step explanation:
the others don't make any sense and also the first one's the only one that's in inequality form.