Answer:
X+Y=26
X-Y=12
Step-by-step explanation:
fiction books= X
non fiction books= Y
then,
fiction books= X
non fiction books = X-12
but Y= X - 12
from. the statement,
X+Y = 26
X-Y=12
B would be correct cause 5 percent would be .66
A because u can clearly see how the line is connected and if u count to where the line is u will see that it is A
Answer: = ( 63.9, 66.7)
Therefore at 90% confidence interval (a,b)= ( 63.9, 66.7)
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.
x+/-zr/√n
Given that;
Mean x = 65.3
Standard deviation r = 5.2
Number of samples n = 36
Confidence interval = 90%
z(at 90% confidence) = 1.645
Substituting the values we have;
65.3 +/-1.645(5.2/√36)
65.3 +/-1.645(0.86667)
65.3+/- 1.4257
65.3+/- 1.4
= ( 63.9, 66.7)
Therefore at 90% confidence interval (a,b)= ( 63.9, 66.7)
