<h3>
Answer: 127</h3>
=================================================
Explanation:
The phrasing "2/3 of 4/5 of his 2nd exam on his 3rd test" is a bit clunky in my opinion. It seems more complicated than it has to be.
The student got 80 on the second exam. 4/5 of this is (4/5)*80 = 0.8*80 = 64. Then we take 2/3 of this to get (2/3)*64 = 42.667 approximately. If we assume only whole number scores are given, then this would round to 43.
Let x be the score on the fourth exam. Since 5 points of extra credit are given, the student actually got x+5 points on this exam.
So we have these scores
- first exam = 70
- second exam = 80
- third exam = 43
- fourth exam = x+5
Adding up these scores and dividing by 4 will get us the average
(sum of scores)/(number of scores) = average
(70+80+43+x+5)/4 = 80
(x+198)/4 = 80
x+198 = 4*80
x+198 = 320
x = 320 - 198
x = 122
So the student got a score of x+5 = 122+5 = 127 on the fourth exam.
We will check if the elevator can hold 10 man
X~(177,32^2)
n= 10
P(SigmaX>172)
SigmaX~(177*10,(32^2)*10)
SigamX~N(1770, 101.19^2)
P(SigmaX>172*10=1720) =Z=(1720-1770)/101.19
Z = -0.49
From Z table Z=-0.49
P(Z=-0.49) = 0.3121 (probability they will not overload)
1- 0.3123 = 0.6879 = 68.79%
The elevator is not safe, the probability to be more the 172 is 68.79%, high probability they could not make it.
Answer:
7
Step-by-step explanation:
Unlikely? it would be 1 out of 52 chances
Answer:
x=-2
sorry i messed up coord val :/
Step-by-step explanation:
