The answer to this question is C
Answer:
the last option
Step-by-step explanation:
can you show the rest of the last option? if there isn't anything cutoff, then the last option would be correct. also, you can use desmos .com next time to help you graph
Answer:
(300 + 50x)/(2 + x)
Step-by-step explanation:
Let the cost of teachers' edition books be t
Let the cost of students' edition books be s
So t = 150; s = 50
Then the total cost of 2 teachers' editions and x students' editions is 2t + sx = 2 × 150 + 50x = 300 + 50x.
The total number of books is 2 + x.
So the average cost per book is (300 + 50x)/(2 + x)
SOLUTION
From the given data the mean is 62 and standard deviation is 4
It is required to find the probability that a data value is between 57 and 62
That is:
The z scores is calculated using:
Using the x values it follows:
Also,
Thus the required probability is:
![P(-1.25The proability is:[tex]P(-1.25This can be expressed as percentage as:[tex]P(-1.25\lt z\lt0.75)=66.8\%](https://tex.z-dn.net/?f=P%28-1.25The%20proability%20is%3A%5Btex%5DP%28-1.25This%20can%20be%20expressed%20as%20percentage%20as%3A%5Btex%5DP%28-1.25%5Clt%20z%5Clt0.75%29%3D66.8%5C%25)
Therefore the correct option is C
