It is m + 9 because if we let m = 60 and the lest was 9 minutes longer than m, the test would be 69 minutes long. Therefore the answer is m + 9
Supplementary = 180 degrees...
A + B = 180
3x + 12 + 7x + 38 = 180
10x + 50 = 180
10 x = 130
x = 13
To find the A just substitute x in...
3 ( 13) + 12
A = 51
To check substitute the x..
A + B = 180
3(13) + 12 + 7(13) + 38 = 180
51 + 129 = 180
180 = 180
Answer:
d. (0.737, 0.823)
The 90% confidence interval is = (0.737, 0.823)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
p+/-z√(p(1-p)/n)
Given that;
Proportion p = 195/250 = 0.78
Number of samples n = 250
Confidence interval = 90%
z value(at 90% confidence) = 1.645
Substituting the values we have;
0.78 +/- 1.645√(0.78(1-0.78)/250)
0.78 +/- 1.645√(0.0006864)
0.78 +/- 1.645(0.026199236630)
0.78 +/- 0.043097744256
0.78 +/- 0.043
(0.737, 0.823)
The 90% confidence interval is = (0.737, 0.823)
