Answer: Mean = 52.8 mins
Step-by-step explanation:
We have lapses of 30 minutes, so we can write the average for each, this means that:
0 < t < 30 can be averaged to the middle of the range: 15 min.
Doing this, we have that:
7 students 15 min
27 students 45 min
12 students 75 min
4 students 105 min.
Now we can calculate the mean:
mean = (x1*n1 + x2*n2 + ...)/N
where x1 is the amount of time 1, and n1 is the number of students associated to that time and so on. N is the total number of students
Mean = (7*15min + 27*45min + 12*75min + 4*105min)/(7 + 27 + 12 + 4)
Mean = 52.8 mins
Answer:
if the numbers are separated by a fraction bar the response should be 11/12th of an hour on Saturday.
Step-by-step explanation:
1/2=6/12
5/12+6/12=11/12
The test statistic for difference between two means is given by:

Thus, the appropriate test statistic is given by:

At 10% level of significance, the rejection region is given by

where:

for 10% level of significance is 1.65
Since z = 1.66 >

, we reject the null hypothesis, which means that <span>the traffic control strategy does not reduce carbon monoxide concentrations by at least 2 ppm.</span>
9^2 (9 to the 2nd power) is 81, 9^6 (9 to the 6th power) is 531441.
Then if we multiply 81*531441 you get 43046721.
Answer:
75
Step-by-step explanation:
\+_+/