Answer:
The 95 percent confidence interval for the mean of the population from which the study subjects may be presumed to have been drawn is (19.1269, 32.6730).
Step-by-step explanation:
Intern No. of Breast
Number Exams Performed X²
1 30 900
2 40 1600
3 8 64
4 20 400
5 26 676
6 35 1225
7 35 1225
8 20 400
9 25 625
<u>10 20 400 </u>
<u> </u><u> ∑ 259 ∑ 7515</u>
Mean= X`= ∑x/n= 259/10= 25.9
Variance = s²= 1/n-1[∑X²- (∑x)²/n]
= 1/0[7515- (259)²/10]= 1/9[7515- 6708.1]
= 806.9/9=89.655= 89.66
Standard Deviation= √89.655= 9.4687
Hence
The value of t with significance level alpha= 0.05 and 9 degrees of freedom is t(0.025,9)= 2.262
The 95 % Confidence interval is given by
x`±t(∝,n-1) s/√n
So Putting the values
25.9± 2.262( 9.4687/√10)
= 25.9 ±2.262 (2.9943)
= 25.9 ± 6.7730
= 25.9 +6.7730=32.6730
25.9 -6.7730= 19.1269
= 19.1269, 32.6730
The 95 percent confidence interval for the mean of the population from which the study subjects may be presumed to have been drawn is (19.1269, 32.6730).
Answer:
She used 87 minutes last month
Step-by-step explanation:
Step 1: Express the total monthly phone bill
The total monthly phone bill can be expressed as follows;
A=F+(R×M)
where;
A=total monthly phone bill
F=fixed income per month
R=additional rate per minute
M=total number of minutes
In our case;
A=$123.75
F=$102 per month
R=$0.25 per minute
M=m
replacing;
123.75=102+(0.25 of m)
123.75=102+(0.25×m)
123.75=102+0.25 m
123.75-102=0.25 m
0.25 m=21.75
m=21.75/0.25
m=87 minutes
She used 87 minutes last month
Answer:
sads
Step-by-step explanation:
Joe has 82 yards of cotton. His friend has 104 more
104 + 82 = 186
186 yards is how much cotton yarn his friend has
hope this helps
This is simplified as follows:
4w + 2x - w + 2x = 3w + 4x