Grouped Frequency Table

Q.

If the classes in a grouped frequency distribution are not continuous, we can make them continuous by finding half of the difference between the upper limit of a class and the lower limit of the next class, and then adding the same to all the lower limits and subtracting it from all the upper limits in the distribution.

1. True
2. False

Q. The class mark for the class interval 70 - 80 is .

1. 85
2. 75
3. 65

Q. Match the frequencies with their class interval for the given data:
{3, 1, 4, 2, 4, 7, 9, 10, 12, 14, 14, 17}

1. 1
2. 2
3. 4
4. 5

Q.

The weekly expenses (₹) of 30 students of a class are given below: 62 , 80 , 110 , 75 , 84 , 73 , 60 , 62, 100 , 87 , 78 , 94 , 117, 86, 65, 68, 90, 80, 118 , 72, 95, 72, 103, 96, 64, 94, 87, 85, 105, 115. Which among the given options is the correct frequency table?

1. $\begin{array}{cc}Weeklyexpenses& NumberofStudents\\ 60-70& 6\\ 70-80& 5\\ 80-90& 5\\ 90-100& 3\\ 100-110& 3\\ 110-120& 4\end{array}$

2. $\begin{array}{cc}Weeklyexpenses& NumberofStudents\\ 60-70& 6\\ 70-80& 5\\ 80-90& 7\\ 90-100& 3\\ 100-110& 3\\ 110-120& 4\end{array}$

3. $\begin{array}{cc}PocketExpense& NumberofStudents\\ 60-70& 6\\ 70-80& 5\\ 80-90& 7\\ 90-100& 5\\ 100-110& 3\\ 110-120& 4\end{array}$

4. $\begin{array}{cc}Weeklyexpenses& NumberofStudents\\ 60-70& 6\\ 70-80& 5\\ 80-90& 5\\ 90-100& 5\\ 100-110& 7\\ 110-120& 4\end{array}$

Q.

Thirty children were asked about the number of hours they watched TV programmes in the previous week. The results were found as follows:
$\begin{array}{cccccccccc}1& 6& 2& 3& 5& 12& 5& 8& 4& 8\\ 10& 3& 4& 12& 2& 8& 15& 1& 17& 6\\ 3& 2& 8& 5& 9& 6& 8& 7& 14& 12\end{array}$
Make a grouped frequency distribution table for this data, taking class width as 5 and one of the class intervals as 5- 10.

1. $\begin{array}{cc}Hours& Numberofchildren\\ 0-5& 11\\ 5-10& 12\\ 10-15& 5\\ 15-20& 2\\ Total& 30\end{array}$
   

2. $\begin{array}{cc}Hours& Numberofchildren\\ 0-5& 10\\ 5-10& 13\\ 10-15& 5\\ 15-20& 2\\ Total& 30\end{array}$

3. $\begin{array}{cc}Hours& Numberofchildren\\ 0-5& 10\\ 5-10& 14\\ 10-15& 4\\ 15-20& 2\\ Total& 30\end{array}$

4. None of the above

Q. Marks of 30 students are listed in the ungrouped distribution as given below.
13, 32, 45, 67, 23, 18, 23, 21, 10, 19, 18, 17, 24, 12, 45, 56, 76, 80, 23, 12, 11, 12, 19, 15, 19, 54, 74, 34, 58, 34.

If this distribution is converted into a grouped frequency distribution, what is the length of the class interval if the number of the class interval is 5?

1. 80
2. 5
3. 14
4. 12

Q. Salaries of 30 people are represented in the grouped frequency distribution table given below.

Salary (In Rupees)	Number of people
5000-10000	5
10000-20000	10
20000-30000	15

How many people salary lie in between ₹10000 to ₹30000?

1. 5
2. 10
3. 15
4. 25

Q. Marks of 30 students are listed in the ungrouped distribution as given below.

18, 32, 54, 67, 23, 1, 23, 21, 10, 19, 81, 17, 24, 12, 45, 65, 67, 80, 23, 12, 11, 12, 21, 3, 10, 45, 47, 34, 85, 43.

If this distribution is converted into grouped frequency distribution, what is the length of class interval if number of class interval is 7 ?

1. 80
2. 5
3. 16
4. 12

Q. Ages of 50 people in a village are given in a grouped frequency table given below.

Ages	No. of People
1 - 10	10
11 - 20	8
21 - 30	15
31 - 40	8
41 - 50	9

If the age of a person is 30, he should be included in ___________.

1. 1st class interval
2. 2nd class interval
3. In both 1st and 2nd class interval
4. 3rd class interval

Q. The following are the heights in centimetres of the students in class X.
162, 155, 166, 173, 170, 161, 166, 151, 167, 176, 178, 175, 163, 165, 170, 152, 172, 166, 176, 159, 157, 158, 148, 174, 152, 162, 171, 178, 157, 145, 148.
The given data has been grouped into class intervals in the given frequency distribution table.
Fill in the table with the missing frequencies.

$\begin{array}{cc}Classinterval& Frequency\left(f_i\right)\\ 145-150& 3\\ 150-155& 3\\ 155-160& p=----\\ 160-165& q=----\\ 165-170& r=----\\ 170-175& s=----\\ 175-180& 5\end{array}$

1. p = 6, q = 4, r = 5, s = 6
2. p = 6, q = 4, r = 4, s = 6
3. p = 5, q = 4, r = 5, s = 6
4. p = 6, q = 5, r = 5, s = 6