Answer: (72.535, 76.665)
Step-by-step explanation:
The confidence interval for population mean is given by :-

, where
= population standard deviation.
n= Sample size
= sample mean.
= Critical z-value (two-tailed)
Given : 
n= 81

The critical values for 90% confidence interval : 
Now, the confidence interval for population mean would be :

Hence, a 90 percent confidence interval estimatefor the average score of all students. : (72.535, 76.665)
Answer:
78
Step-by-step explanation:
Adult tickets = x
Child tickets = 3(Adult tickets) = 3x
The cost of child admission is $5.50, and the cost of adult admission is $8.80. Multiply the cost of admission by the variables and set equal to the total sales.
8.8(x) + 5.5(3x) = 663.6
8.8x + 16.5x = 663.6
25.3x = 663.6
x = 26
Child tickets = 3x
Child tickets = 3(26)
Child tickets = 78
78 child tickets were sold that day.
Answer:
64 quarts
Step-by-step explanation:
(16) / (1/4) = 64
You have a base that is 8x8 and the slant height of the triangle is 22.
This is the formula, L=1/2Ph
H = 22 Meters
1. P=2L+2W -> 2(8)+2(8) = 32 meters
2. L= 1/2(32)(22) = 352 meters squared :)