Using traditional methods it takes 9898 hours to receive an advanced flying license. a new training technique using computer aided instruction (cai) has been proposed. a researcher used the technique on 100 students and observed that they had a mean of 97 hours. assume the population variance is known to be 49.
1. is there evidence at the 0.05 level that the technique performs differently than the traditional method?
2. find the value of the test statistic. round your answer to two decimal places.

1. Yes, the technique performs differently than the traditional method.

2. 0.20

Step-by-step explanation:

The null hypothesis  

H0 = mean is 97 hours

Ha = mean > 97

Let´s make the z test

z = (x – mean) / standard deviation / √sample size

z = (97 – 98) / 49 / √100

z = -0.204

Confidence level of 95%, that means the the siginficance level α is 1 – p

α = 1 – 0.95 = 0.05

Z(α /2) = Z(0.05/2) = Z (0.025)

Using a z table Z = 1.96

since our calculated z values is smaller than the critical value, the null hypothesis can be rejected. Sample mean is different from sample population so the technique performs differently than the traditional method.

a.   we have two

lines:   y = 4-x   and  

y = 8-x^-1

given two simultaneous equations that are both to be

true, then the solution is the points where the lines cross. the intersection is

where the two equations are equal. therefore the solution that works for both

equations is when

4-x = 8-x^-1

this is where the two lines will cross and that is the

common point that satisfies both equations.

b.   4-x = 8-x^-1

  x           4-x       8-x^-1

-3           7        

8.33

-2           6         8.5

-1           5         9

  0           4        

-

  1           3        

7

  2           2        

7.5

  3           1         7.67

the table shows that none of the x values from -3 to 3 is

the solution because in no case does

4-x = 8-x^-1

to find the solution we need to rearrange the equation to

find for x:

4-x = 8-x^-1

multiply both sides with x:

4x-x^2 = 8x-1

x^2+4x-1=0

x= -4.236, 0.236

therefore there are two points that satisfies the

equation.

find y:  

x=-4.236

y = 4-x   = 4 – (-4.236)

= 8.236

y = 8-x^-1 =   .236)^-1

= 8.236

x=0.236

  y = 4-x   = 4 – (0.236) = 3.764

y = 8-x^-1 =   8-(0.236)^-1

= 3.764

thus the two lines cross at 2 points:

(-4.236, 8.236) & (0.236, 3.764)

c.   to solve

graphically the equation 4-x = 8-x^-1

we would graph both lines: y = 4-x   and   y

= 8-x^-1

the point on the graph where the lines cross is the

solution to the system of equations.

just graph the points on part b on a cartesian coordinate

system and extend the two lines.   the

solution is, as stated, the point where the two lines cross on the graph.

step-by-step explanation:

mark brainliest!

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step-by-step explanation: