Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-
Given : Sample size : n= 35 , large sample (n>30)
Mean difference : 
Standard deviation : 
Significance level : 
Critical value : 
Now, the 99.9% confidence interval for the mean difference between the marks scored last week and marks scored this week by all the students will be :-
Hence, the 99.9% confidence interval for the mean difference between the marks scored last week and marks scored this week by all the students =
Answer:
125 miles
Step-by-step explanation:
1) 675-425 = 250
2) 250/2 = 125
3) 125 miles before she needs to stop
Answer:
1.22
Step-by-step explanation:
Since there is one whole shaded. And 2 tens, and 2 ones. Its 1.22.
Each pack of batteries cost $21 each.
And then you have $63.
The operation to be used: Division.
63 ÷ 21 ==
Answer: 3
= You can buy 3 packs of batteries with your $63.
a) (0.17 ac)×(126 min/ac) = 21.42 min
b) I can mow 1/126 ac/min; you can mow 1/117 ac/min. Together, we can mow at a rate that is the sum of these:
... (1/126 + 1/117) ac/min = (117 + 126)/(126×117) = 243/14,742 ac/min
Then it will take 14,742/243 min/ac × 0.17 ac/lawn ≈ 10.31 min/lawn
