-3+12-2=7 i believe is the number sentence idk if that’s what you’re asking for
Answer:
The score on the next test must be between 86 and 98, inclusive
Step-by-step explanation:
Write an inequality using the average:
86 ≤
≤ 90
Solve for x:
multiply everything by 3:
258 ≤ x + 83 + 89 ≤ 270
258 ≤ x + 172 ≤ 270
subtract 172 from everything:
86 ≤ x ≤ 98
The score on the next test must be between 86 and 98, inclusive
Answer:
The probability that the mean daily revenue for the next 30 days will exceed $7500 is 0.0855
Step-by-step explanation:
It has been given that
![\mu=7200\\\\\sigma=1200,n=30,x=7500](https://tex.z-dn.net/?f=%5Cmu%3D7200%5C%5C%5C%5C%5Csigma%3D1200%2Cn%3D30%2Cx%3D7500)
Now, the formula for z-score of a normal distribution is given by
![z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}](https://tex.z-dn.net/?f=z%3D%5Cfrac%7Bx-%5Cmu%7D%7B%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D%7D)
Substituting the known values, we get
![z=\frac{7500-7200}{\frac{1200}{\sqrt{30}}}](https://tex.z-dn.net/?f=z%3D%5Cfrac%7B7500-7200%7D%7B%5Cfrac%7B1200%7D%7B%5Csqrt%7B30%7D%7D%7D)
Simplifying, we get
![z=\frac{300}{219.1}\\\\z=1.369238](https://tex.z-dn.net/?f=z%3D%5Cfrac%7B300%7D%7B219.1%7D%5C%5C%5C%5Cz%3D1.369238)
Now, we have to find that the daily revenue for next 30 days will exceed $7500.
Thus, we have to find
P(z>1.369238)
From the normal distribution table, we have
P(z>1.369238)= 0.0855
Therefore, required probability is 0.0855
Easy, 2 times 4/5 is 2/1 time 4/5 = 8/5 or 1 3/5