Answer:
the answer is 3
Step-by-step explanation:
is this a joke
Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
Hello,
aPb=b*(b-1)*(b-2)*....*(b-a+1) / a!
3P5=5*4*3/(3*2*1)=10
If we name the number of the employers 1,2,3,4,5
Here are the choices:
123,124,125,134,135,145,234,235,245,345 (total 10 choices)
Hey,
If you were to divide 137/7 it would be it would be 19 or if you wont a decimal it would be 19.5
I Hoped that Helped
He is wrong.
The 10 inch cube is bigger than the 5 inch cube by 5 cm in EACH DIRECTION.
So, the 10 inch cube should be twice as big in volume by a factor of 2*2*2
=8
Okay let's see.
5 cm cube volume = 5*5*5 = 125 cc
10 cm cube volume = 10 * 10 * 10 = 1,000 cc
1,000 / 125 = 8