Persian History began with Medes.
Answer:
The LCM of 3 and 7 is 21.
Step-by-step explanation:
Answer:
(a)


(b)
B. The sample is too small to make judgments about skewness or symmetry.
Step-by-step explanation:
Given:


Solving (a):
First, calculate the difference between the recorded TBBMC for both operators:

The last row which represents the difference between 1 and 2 is calculated using absolute values. So, no negative entry is recorded.
The mean is then calculated as:




Next, calculate the standard deviation (s).
This is calculated using:

So, we have



Solving (b):
Of the given options (A - E), option B is correct because the sample is actually too small
15/30 brushed their teeth more than twice a day.
Fraction 1/2 <- (Simply by dividing by HCF)
Percentage= 50% (15 divided by 30 multiplied by 100) or you realise the 15 is half of 30. A half is 50%
Decimal= 0.5 (50% divided by 100)