Answer: 21
Step-by-step explanation:
Answer:
2.275%
Step-by-step explanation:
The first thing to do here is to calculate the z-score
Mathematically;
z-score = (x-mean)/SD
from the question, x = 12,300 hours , mean = 11,500 hours while Standard deviation(SD) = 400 hours
Plugging the values we have;
z-score = (12,300-11,500)/400 = 800/400 = 2
Now, we want to calculate P(z ≤ 2)
This is so because we are calculating within a particular value
To calculate this, we use the z-score table.
Mathematically;
P(z ≤ 2) = 1 - P(z > 2) = 1 - 0.97725 = 0.02275
To percentage = 2.275%
Answer:
A. d ≤ –7 or d > 8.
Step-by-step explanation:
Given : 2d + 3 ≤ –11 or 3d – 9 > 15.
To find : What are the solutions of the compound inequality .
Solution : We have given 2d + 3 ≤ –11 or 3d – 9 > 15.
For 2d + 3 ≤ –11
On subtracting both sides by 3
2d ≤ –11 - 3 .
2d ≤ –14.
On dividing both sides by 2 .
d ≤ –7.
For 3d – 9 > 15.
On adding both sides by 9.
3d > 15 + 9 .
3d > 24 .
On dividing both sides by 3 .
d > 8 .
So, A. d ≤ –7 or d > 8.
Therefore, A. d ≤ –7 or d > 8.
