Answer:
Step-by-step explanation:
Sample proportion p is the proportion of favourable numbers to total number in the sample
By central limit theorem and also approximation of binomial to normal , we have sample proportion for large number of samples will be normal
with mean = sample proportion
and std deviation = 
Thus we find standard deviation of proportion sample is inversely proportional to the square of the sample size n.
It follows automatically that as sample size increases std deviation decreases.
Here from 80 sample size was made to 200
So std deviation would decrease automatically
Answer:
21 students per teacher
10 students per tutor
10 tutors needed for 110 students
Step-by-step explanation:
84 ÷4=21
30÷3=10
110÷10=10
The answer would be 3.
<span>k^2 + 5k + 6 = (k + 2) (k + 3)
HOPE THIS HELPS! ^_^</span>
Answer:
This question is impossible
Step-by-step explanation:
Answer:
- 1 bus, 72 vans
- $6960 is the minimum cost
Step-by-step explanation:
A bus costs over $19 per student; a van costs less than $12 per student. The required number of students could be transported by 81 vans, but that requires 81 chaperones.
Since there are only 80, and a bus requires fewer chaperones per student, we can reduce the number of required chaperones to an acceptable level by employing one bus. 1 bus replaces 9 vans, and requires 1 less chaperone than 9 vans.
The minimum cost is 1 bus and 72 vans. That cost is $1200 +72×$80 = $6960.
