Answer:
a) 16%
b) 2.5%
Step-by-step explanation:
a)
The mean is 70 with standard deviation(SD) of 3 and you are asked to find out the percentage of staff that have <67(70-3 inch= mean - 1 SD) inch size, which means 1 SD below the mean (<-1 SD). Using 68-95-99.7 rule, you can know that 68% of the population is inside 1 SD range from the mean ( -1 SD to + 1 SD).
To put it on another perspective, there are 32% of the population that have < -1 SD and > +1 SD value. Assuming the distribution is symmetrical, then the value of < - 1 SD alone is 32%/2= 16%
b)
The question asks how many populations have size >76 inches, or mean + 2 SD (70+3*2 inch).
You can also solve this using 68-95-99.7 rule, but you take 95% value as the question asking for 2 SD instead. Since 95% of population is inside 2 SD range from the mean ( -2 SD to + 2 SD), so there are 5% of population that have < -2 SD and > +2 SD value. Assuming the distribution is symmetrical, then the value of > +2 SD alone is 5%/2= 2.5%
Answer:
300 students are enrolled.
Step-by-step explanation:
As the university accepts 60% of the students who apply.
As 2000 students apply, it means that:
2000 × 60% ⇒ 2000 × 0.6 = 1200 students are accepted
Out of these 1200, 25% enrolled
1200 × 25% ⇒ 1200 × 0.25 = 300 students are enrolled
Therefore, 300 students are enrolled.
834 ➗ 2 =417. I hope I helped :)