Answer:
0.9586
Step-by-step explanation:
From the information given:
7 children out of every 1000 children suffer from DIPG
A screening test designed contains 98% sensitivity & 84% specificity.
Now, from above:
The probability that the children have DIPG is:
= (0.98 × 0.007) + 0.16( 1 - 0.007)
= 0.16574
So, the probability of not having DIPG now is:
= 0.9586
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
That is z with a pvalue of , so Z = 1.28.
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.