Answer:
2.51 < σ < 3.92
Step-by-step explanation:
We will use Chi-Square distribution to create the interval. We have the following information:
n = 41
Level of Confidence : 95%,
This corresponds to Chi-Square values of:
24.433 for the left tail and 59.342 for the right tail
We need to calculate the sample Variance. This is done on attached photo 1 (the shortcut formula for finding variance was used)
We get s = 9.3866.
See the construction of the confidence interval on the second attached photo
Area of a trapezoid: (top + bottom)/2 x height
Area = (6.5 + 15.1)/2 x 5
Area = 21.6/2 x 5
Area = 10.8 x 5
Area = 54 square inches.
Answer:
7.99
Step-by-step explanation:
x^2 +3x
Let x=1.7
(1.7)^2 +3(1.7)
2.89+5.1
7.99