Answer: -9.1
Explanation
-3x +12.4=39.7
First minus 12.4 from both sides
-3x +12.4=39.7
-12.4 -12.4
-3x=27.3
Now devid both sides by -3
X= -9.1
V = length×width ×height
V = 9 × 2 × 3
V = 54 units cubed
Trigonometry:
We know that csc x = 1 / sin x and π = 180°;
sin 5π/ 6 = sin 150° = 1/2
csc 2π / 3 = 1 / sin 120° = 1 / √3/2 = 2 / √3
Finally:
4 · 1/2 + 7 · ( 2 / √3 )² = 2 + 7 · 4/3 =
= 2 + 28/3 = 2 + 9 1/3 = 11 1/3
Answer:



Step-by-step explanation:
Given

Solving (a): Point estimate of difference of mean
This is calculated as: 


Solving (b): 90% confidence interval
We have:


Confidence level is: 



Calculate 


The z score is:

The endpoints of the confidence level is:






Split


Hence, the 90% confidence interval is:

Solving (c): 95% confidence interval
We have:


Confidence level is: 



Calculate 


The z score is:

The endpoints of the confidence level is:






Split


Hence, the 95% confidence interval is:

Answer:
14,820
Step-by-step explanation:
A year has 52 weeks. 285 x 52 = 14820