Answer:
Step-by-step explanation:
2.72 is the unit rate
Solution:
Given the mean and standard deviation;

The z-score formula is;

(a)

(b)

(c)
The expression 36x² - 121 is in the 'difference of two squares form' which is (a² - b²)
Factorising (a² - b²) gives (a+b)(a-b)
Factorising 36x² - 121 gives (6x+11)(6x-11)
Answer:
Step-by-step explanation:
If two ratios make a proportion then it can be shown as:
Let's verify the answer choices with this method
A. 1/4 and 5/25
- 1*25 = 4*5
- 25 = 20, incorrect, not a proportion
B. 1/4 and 7/24
- 1*24 = 4*7
- 24 = 28, incorrect, not a proportion
C. 1/4 and 10/48
- 1*48 = 4*10
- 48 = 40, incorrect, not a proportion
D. 1/4 and 9/36
- 1*36 = 4*9
- 36 = 36, correct, this is a proportion
Answer:
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159
Step-by-step explanation:
According to the given data we have the following:
mean = μ= 22
standard deviation = σ = 2
n = 100
μx = 22
σx=σ/√n=2/√100=0.2
Therefore, P( x < 21.8)=P(x-μx)/σx<(21.8-22)/0.2
=P(z<-1)
= 0.159
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159