Answer:
29. 15.87%
30. 4.75%
31. 0.62%
32. probability cannot be calculated (0%)
Step-by-step explanation:
We have that the formula of the normal distribution is:
z = (x - m) / sd
where x is the value we are going to evaluate, m is the mean and sd is the standard deviation
x = 16 and m = 16.5
when sd = 0.5
z = (16 - 16.5) /0.5
z = -1
Now when looking in the z table, we have that the corresponding value is 0.1587, that is, the probability is 15.87%
when sd = 0.3
z = (16 - 16.5) /0.3
z = -1.67
Now when looking in the z table, we have that the corresponding value is 0.0475, that is, the probability is 4.75%
when sd = 0.2
z = (16 - 16.5) /0.2
z = -2.5
Now when looking in the z table, we have that the corresponding value is 0.0062, that is, the probability is 0.62%
when sd = 0
z = (16 - 16.5) / 0
z = infinity
probability cannot be calculated
Answer:
There are 40 problems on the test
Step-by-step explanation:
Let p = the number of problems on the test
The number of problems on the test times the percent correct is the number correct
p * 85% = 34
p * .85 = 34
Divide each side by .85
p * .85/.85 = 34/.85
p = 40
There are 40 problems on the test
Answer:
ABC is isosceles
Step-by-step explanation: