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/Step-by-step explanation:
Area of trapezium = ½*(AD + BC)*AB
Area = 42 cm²
AD = (x + 8) cm
BC = (x + 5) cm
AB = x cm
Plug in the values into the equation
42 = ½((x + 8) + (x + 5))*x
42 = ½((x + 8 + x + 5)*x
42 = ½(2x + 13)*x
Multiply both sides by 2
42*2 = (2x + 13)*x
84 = 2x² + 13x
2x² + 13x = 84
Subtract both sides by 84
2x² + 13x - 84 = 0
21 = 3.7
35 = 5.7
probably the factors have 3.5.7
= 105
let's try :
1 . 105
3 . 35
5 . 21
7 . 15
Yep, correct.
Answer:
no
Step-by-step explanation:
A trapezoid is shown, not a bag. If we assume that this shape is supposed to be the front of the bag, Mariam does NOT have enough pink fabric to make the front of the bag from pink fabric.
The area of the trapezoid shown is ...
A = (1/2)(b1 +b2)h
A = (1/2)(9 in + 8 in)(15 in) = 127.5 in^2
This area is larger than the amount of fabric Mariam has, so she does not have enough.
Answer:
Step-by-step explanation:
Given
From the rows, the equation is:
--- (1)
--- (2)
--- (3)
Make A the subject in:
Substitute in
Make B the subject
Substitute in
Collect like terms
Divide by 9
Recall that:
Recall that:
Hence:
