The sample of 81 students was selected with a mean score of 90, this illustrates an example of a right tailed one sample z test.
<h3>How to illustrate the sample?</h3>
From the information given, the teacher claims that the mean score of students in his class is greater than 82 with a standard deviation of 20. In this case, the right tailed one sample z test is used.
The z value will be:
= (90 - 82)/20/✓81
= 3.6
Since 3.6 > 1.645, the null hypothesis will be rejected as there's enough evidence to support the teacher's claim.
When an online medicine shop claims that the mean delivery time for medicines is less than 120 minutes with a standard deviation of 30 minutes, the left tailed one sample test is used.
The z value will be:
= (100 - 120)/(30/✓49)
= -4.66
The null hypothesis is rejected as there is enough evidence to support the claim of the medicine shop.
Learn more about sampling on:
brainly.com/question/17831271
#SPJ1
Answer:critical stress= 20.23 MPa
Explanation:
Since there was an internal crack, we will divide the length of the internal crack by 2
Length of internal crack, a = 0.7mm,
Half length = 0.7mm/2= 0.35mm changing to meters becomes
0.35/ 1000= 0.35 x 10 ^-3m
The formulae for critical stress is calculated using
σC = (2Eγs /πa) ¹/₂
σC = critical stress=?
Given
E= Modulus of Elasticity= 225GPa =225 x 10 ^ 9 N/m²
γs= Specific surface energy = 1.0 J/m2 = 1.0 N/m
a= Half Length of crack=0.35 x 10 ^-3m
σC= (2 x 225 x 10 ^ 9 N/m² x 1.0 N/m /π x 0.35 x 10 ^-3m)¹/₂
=(4.5 x 10^11/π x 0.35 x 10 ^-3)¹/₂
=(4.0920 x10 ^14)¹/₂
σC=20.23 x10^6 N/m² = 20.23 MPa
Answer:
35 miles
Explanation:
When you are driving a truck that has an air brake system you have to keep in mind that when driving down a steep downgrade, the truck will automatically accelerate due to the inclination of the road, so in order to keep the speed to a controllable situation, you need to activate the service brake until you've reached the 35 miles per hour mark.
‼️‼️‼️thank u for the freebie lolllll shdisndidneidn