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 ]
The coefficient matrix is build with its rows representing each equation, and its columns representing each variable.
So, you may write the matrix as
which means
The determinant is computed subtracting diagonals:
So, we have
Answer:
84
Step-by-step explanation:
f(x) = 3x^2 + 2x – 1
Let x=5
f(5) = 3(5)^2+2(5) -1
= 3*25 +10-1
= 75+10 -1
= 85 -1
Answer:
x = 1/2 , x = -1/2
Step-by-step explanation:
Given equation;
169x² - 42.25
Find:
Solution of equation using square root
Computation:
169x² - 42.25
We know that 13² = 169 and 6.5² = 42.25
So,
[13x]² - [6.5]²
a² - b² = (a + b)(a - b)
So,
[13x]² - [6.5]² = [13x + 6.5][13x - 6.5]
So,
13x + 6.5 = 0 , 13x - 6.5 = 0
x = 6.5 / 13 , x = -6.5 / 13
x = 1/2 , x = -1/2