Vicky’s average speed is 0.55m/h
Answer:
c
Step-by-step explanation:
Answer:
We have strong evidence that on average, students study less than 150 minutes per night during the school week
Step-by-step explanation:
Normal distribution:
mean μ₀ = 150
Sample:
Sample size n = 272
Sample mean x = 141
Sample standard deviation s = 66
The standard error of the sample mean SE = σ /√n
SE = 66/√272
SE = 66 / 16,49
SE = 4
Test Hypothesis:
Null hypothesis H₀ x = μ₀
Alternative hypothesis Hₐ x < μ₀
z(s) test statistics is:
z(s) = ( x - μ₀ ) / s/√n
z(s) = - 9 /4
z(s) = - 2,25
p-value for that z(s) p-value = 0,0122
Then for α = 0,05 p-value < 0,05
We are in the rejection region we need to reject H₀
Answer:
18 and 40
Step-by-step explanation:
Let x be the age of Claire and y the age of her mother
Claire's mother is 4 years more than twice Claire's age
The sum of their ages are is 58
the system is:
Multiply (y+x = 58) by -1 and then add it to (y = 2x+4) to eliminate y
- -y-x = -58
- -y-x+y = 2x+4-58
- -x -2x = -54
- -3x = -54
- x = 54/3
- x = 18
y= 58-18 = 40
so claire's mother is 40 years old and claire is 18
Answer:
second
Step-by-step explanation:
