Answer:
Kindly check explanation
Step-by-step explanation:
Given that :
Mean (m) = 72
Standard deviation (sd) = 10
Grading cutoff policy:
bottom 5% receive F
next 15% receive D
next 35% receive C
next 30% receive B
A) Give the cutoffs for the grades in this course in terms of standardized scores.
Standardized score for grade cutoff:
Locating the Zscore for the proportions on the z table :
Bottom 5% = 0.05 ; corresponding Zscore = - 1.645
next 15% receive D = (5 +15)% 0.20 ; corresponding Zscore = - 0.84
next 35% receive C = (20+35)% = 0.55 ; corresponding Zscore = 0.13
next 30% receive B = (55 + 30)% = 0.85 ; Corresponding Zscore = 1.04
B) Give the cutoffs in terms of actual total scores.
Recall:
Zscore = (x - m) /sd ; where x = actual score
x = sd*z + m
For F:
10*(-1.645) + 72 = 55.55
For D:
10*(-0.84) + 72 = 63.6
For C:
10*(0.13) + 72 = 73.3
For B:
10*(1.04) + 72 = 82.4
C) Do you think that this method of assigning grades is a good one?
Yes, it is good in terms of expressing scores around the mean such that score below are negative and those above are positive. However, it is a little bit ambiguous.
84 words = 2 min
1 word = 2/84 = 1/42
420 words = 1/42 x 420 = 10 mins
Answer: 10 mins
Complete Question
It takes 28minutes for 7 people to paint 7 walls. How many minutes does it take 14 people to paint 14 walls?
Answer:
28 minutes
Step-by-step explanation:
It takes 28minutes for 7 people to paint 7 walls.
Hence, the today number of minutes for 1 person to paint the wall =>
7 people = 28 minutes
1 person = 28 minutes × 7 people =
198 people minutes = 7 walls
1 wall = 198 /7
1 wall = 28 people minutes
How many minutes does it take 14 people to paint 14 walls?
From the above calculation,
1 wall = 28 people minutes
14 walls =
= 14 walls × 28 people minutes/14 People
= 28 minutes
Therefore, it would take 28 minutes for 14 people to paint 14 walls.
Answer:
2/5, 8/20, 4/10,16/40
Step-by-step explanation:
40%
Percent means out of 100
40/100 = 4/10 = 2/5
Lets look at the choices
8/100 =4/50 =2/25 not equal
2/5 equal
8/20 = 4/10 =2/5 = equal
4/10 = 2/5 = equal
16/40 = 4/10 = 2/5 equal
