Answer:
E
Step-by-step explanation:
Solution:-
- We are to investigate the confidence interval of 95% for the population mean of walking times from Fretwell Building to the college of education building.
- The survey team took a sample of size n = 24 students and obtained the following results:
Sample mean ( x^ ) = 12.3 mins
Sample standard deviation ( s ) = 3.2 mins
- The sample taken was random and independent. We can assume normality of the sample.
- First we compute the critical value for the statistics.
- The z-distribution is a function of two inputs as follows:
- Significance Level ( α / 2 ) = ( 1 - CI ) / 2 = 0.05/2 = 0.025
Compute: z-critical = z_0.025 = +/- 1.96
- The confidence interval for the population mean ( u ) of walking times is given below:
[ x^ - z-critical*s / √n , x^ + z-critical*s / √n ]
Answer: [ 12.3 - 1.96*3.2 / √24 , 12.3 + 1.96*3.2 / √24 ]
Answer:
2kg
Step-by-step explanation:
Let the sum of the other 2 bricks be R. Given that the heaviest brick weighs 2/3 times as much as the other 2 bricks in total, then the weight of the heaviest brick H in terms of the weight of the other 2 will be
H = 2/3 * R
= 2R/3
Given that the 3 bricks weigh 5kg in total then,
2R/3 + R = 5
Multiply through the equation by 3
2R + 3R = 15
5R = 15
Divide both sides by 5
R = 15/5
= 3
The weight of the heaviest brick is 2R/3. Since R = 3, the heaviest block weighs
= 2 * 3/3
= 2kg
Answer:
0=0 1=1 <u> 6<8</u>
Since 6 < 8 0.16 < 0.18
so, the hummingbird weighs more than a nickel
Step-by-step explanation:
6 is less than 8 so therefore .16 is less than .18. The nickel weighs .18 and .16 is less than that.
Given equation, y = – 1.3(x + 3)2 – 9 is in slope intercept form.
Step-by-step explanation:
Slope intercept form standard formula:
y = mx + c
where,
y= y intercept
x= x intercept
m = slope
c = constant
We are given:
y = - 1.3(x + 3)2 - 9
y = - 2.6x + 7.8 - 9
y = -2.6x -1.2
So,
Slope = m = -2.6
constant = 1.2
Answer:
x ≈ 8.7
Step-by-step explanation:
Using the sine ratio in the right triangle
sin75° = 
= 
= 
( multiply both sides by 9 )
9 × sin75° = x , then
x ≈ 8.7 ( to the nearest tenth )
