Answer: 0.0793
Step-by-step explanation:
Let the IQ of the educated adults be X then;
Assume X follows a normal distribution with mean 118 and standard deviation of 20.
This is a sampling question with sample size, n =200
To find the probability that the sample mean IQ is greater than 120:
P(X > 120) = 1 - P(X < 120)
Standardize the mean IQ using the sampling formula : Z = (X - μ) / σ/sqrt n
Where; X = sample mean IQ; μ =population mean IQ; σ = population standard deviation and n = sample size
Therefore, P(X>120) = 1 - P(Z < (120 - 118)/20/sqrt 200)
= 1 - P(Z< 1.41)
The P(Z<1.41) can then be obtained from the Z tables and the value is 0.9207
Thus; P(X< 120) = 1 - 0.9207
= 0.0793
Answer:
3.93 per hour
Step-by-step explanation:
The first 4 hours is at 20 hours / 4 hours or 5 dollars an hours
The second line has a slope of 2.50 dollars an hour
But there is also a surcharge when you go over 4 hours
That is a 5 dollar flat rate at 4 hours
Assuming that we do not include the flat rate in the hourly calculation
4 hours * 5 dollar + 3 hours * 2.50 = 20+7.50
27.50 is the hourly charge
Divide by 7 hours
3.928571429
3.93 per hour
Answer:
149.5, 150.5 , 151.5, 152.5
Step-by-step explanation:
n+(n+1)+(n+2)+(n+3)= 604
Combine Like Terms
4n + 6 = 604
Subtract 6
4n = 598
Divide by 4
n=149.5
Check Your Work:
149.5+150.5+151.5+152.5 = 604
