Statistics-And-Probability Question 623
Question: An aeroplane flies around a squares, the sides of which measure 100 miles each. The aeroplane covers at speed of 100 m/h the first side, at 200 m/h the second side. At 300 m/h the third side and 400 m/h the fourth side. The average speed of the aeroplane around the square is
Options:
A) 900 m/h
B) 195 m/h
C) 192 m/h
D) 200 m/h
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Using the weighted HM formula $ \frac{1}{H}=\frac{1}{N}\sum\limits_{i=1}^{n}{\frac{f_{i}}{x_{i}}orH=\frac{1}{\frac{1}{N}\sum\limits_{i}{\frac{f_{i}}{x_{i}}}}} $
$ \therefore $ Average speed $ =\frac{400}{100( \frac{1}{100}+\frac{1}{200}+\frac{1}{300}+\frac{1}{400} )} $ $ =192m/h $
BETA
