Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
µ = 12
For the alternative hypothesis,
µ < 12
Since the population standard deviation is given, z score would be determined from the normal distribution table. The formula is
z = (x - µ)/(σ/√n)
Where
x = sample mean
µ = population mean
σ = population standard deviation
n = number of samples
From the information given,
µ = 12 minutes
x = 8 minutes
σ = 12 minutes
n = 36
z = (8 - 12)/(12/√36) = - 4/2 = - 2
Test statistic = - 2
Answer: A=16
Step-by-step explanation:
24=a+8
-a=8-24
-a=-16
Answer:
x=64
y=40
Step-by-step explanation:
2x+x-12=180
3x=192
x=64
3y+y+20=180
4y=160
y=40
Answer:
5
Step-by-step explanation:
y= 4x+17
73=4x+17 (subtract 17 by both sides)
20=4x (divide by both sides)
5= x, 5 days
