Grouping data - class-X
Covers frequency distribution, measures of central tendency, and data interpretation for grouped data
Questions
Tally marks are used find
- class interval
- range
- frequency
- upper limit
Satish got the following marks in his weekly class tests out of $50$:
$48$, $32$, $36$, $42$, $38$, $35$, $39$, $49$, $34$, $14$, $32$, $37$, $31$ What should he expect in the next weekly test out of the following?
(i) between $40 - 50$
(ii) between $30 - 40$
- Between $40-50$
- Between $30-40$
- Data insufficient
- None of these
| 12 | 24 | 36 | 48 | 60 | 72 |
|---|---|---|---|---|---|
| 24 | 48 | 60 | 72 | 50 | 30 |
| 50 | 45 | 50 | 75 | 50 | 34 |
The number of students in a quiz competition scores are in the table. How many students scored $50$ marks?
- $4$
- $5$
- $8$
- $3$
Consider the following frequency distribution:
| Class | $0-10$ | $0-20$ | $0-30$ | $0-40$ | $0-50$ |
|---|---|---|---|---|---|
| Frequency | $3$ | $8$ | $14$ | $20$ | $25$ |
What is the above frequency distribution known as?
- Cumulative distribution in more than type
- Cumulative distribution in less than type
- Continuous frequency distribution
- None of the above
Consider the following statements :
1. A continuous random variable can take all values in an interval.
2. A random variable which takes a finite number of values is necessarily discrete.
3. Construction of a frequency distribution is based on data which are discrete.
Which of the above statements are correct ?
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
The marks (out of 10) obtained by 28 students in a Mathematics test are listed as below :
8, 1, 2, 6, 5, 5, 5, 0, 1, 9, 7, 8, 0, 5, 8, 3, 0, 8, 10, 10, 3, 4, 8, 7, 8, 9, 2, 0
The number of students who obtained marks more than or equal to 5 is
- 13
- 15
- 16
- 17
The frequency distribution of marks obtained by $60$ students of a class is given.
| X | $30-34$ | $40-44$ | $45-49$ | $50-54$ | $55-59$ | $60-64$ |
|---|---|---|---|---|---|---|
| f | $3$ | $5$ | $12$ | $18$ | $14$ | $62$ |
Find mode of the distribution.
- $42.50$
- $52.50$
- $52.05$
- $42.05$
The median and mode of frequency distribution are 525 and 500, then mean of same frequency distribution is -
- 75
- 107.5
- 527.5
- 537.5
Mode of distribution
$Marks\begin{bmatrix} 4 & 5 & 6 & 7 & 8 \end{bmatrix}\ No\quad of\quad students\quad \begin{bmatrix} 3 & 5 & 10 & 6 & 1 \end{bmatrix}$
- 6
- 10
- 8
- 4
The cumulative frequency distribution corresponding to 20 percentile is ______.
- 10%
- 20%
- 25%
- 33%
Find a 9596 confidence interval for the population mean from the following data:
Sample size n = 65, Mean = 6300, Standard deviation = 9.5, N=1000.
- (6298 - 6302)
- (6301 - 6308)
- (6290 - 4310)
- (6288 - 6315)
What are the shortcomings of frequency distribution?
- it does not show the details that are found in raw data
- Once the data are grouped into classes, an individual observation has no significance in further statistical calculations
- Statistical calculations are based only on the values of the class mark and not on the values of the observations in that class
- All of these
A tabular summary of a set of data showing classes of the data and the fraction of the items belonging to each class is called ______________.
- the class width
- a relative frequency distribution
- a cumulative relative frequency distribution
- on ogive
In a truly normal frequency distribution _________.
- the mean always is the same as the standard deviation
- the mean is never the same as the mode
- the mode is never the same as the median
- the mean always is the same as the median