Tag: statistics
Questions Related to statistics
To find the concentration of $SO _2$ in the air (in parts, per
million), the data was collected for 30 localities, in a certain city
and is presented below:
Concentration of $SO _2$ (in ppm) | Frequency |
---|---|
0.00-0.04 | 4 |
0.04-0.08 | 9 |
0.08-0.12 | 9 |
0.12-0.16 | 2 |
0.16-0.20 | 4 |
0.20-0.24 | 2 |
Find the mean concentrations of $SO _2$ in the air.
The following table gives the per day income of 50 pupils. Find the arithmetic mean of their per day income.
Income/day (Rs) | 70-74 | 74-78 | 78-82 | 82-86 | 86-90 |
---|---|---|---|---|---|
No. of people | 8 | 10 | 11 | 17 | 4 |
Compute the missing frequencies $'f _1'$ and $'f _2'$ in the following data, if the mean is $166\frac {9}{26}$ and the sum of the observation is 52.
Classes | Frequency |
---|---|
140-150 | 5 |
150-160 | $f _1$ |
160-170 | 20 |
170-180 | $f _2$ |
180-190 | 6 |
190-200 | 2 |
Total | 52 |
In a frequency dist. if $\displaystyle d _{i}$ is deviation of variates from a number e and mean = $\displaystyle e+\frac{\Sigma f _{i}d _{i}}{\Sigma f _{i}}$, then e is
If the mean of four observations is $20$ and when a constant is added to each observation the mean becomes $22$ The value of $c$ is?
HM of 3 and 5 is
GM of 4 and 64 is
The harmonic mean of 20 and 30 is
Find the sum of 5 geometric means between $\displaystyle\frac{1}{3}$ and 243, by taking common ratio positive.
The geometric mean of $10$ observations on a certain variable was calculated as $16.2$. It was later discovered that one of the observations was wrongly recorded as $12.9$; infact it was $21.9$. The correct geometric mean is: