Class 9th math 12.2 solution english PCTB

Question # 01: Find the arithmetic mean in each of the following:

\( (i) \; \) 4, 6, 10, 12, 15, 20, 25, 28, 30

\( (ii) \; \) 12, 18, 19, 0, -19, -18, -12

\( (iii) \; \) 6, 5, 11, 12.3, 9, 8.1, 16, 18, 20.5, 25

\( (iv) \; \) 8, 10, 12, 14, 16, 20, 22

Question 2: Following are the heights in (inches) of 12 students. Find the median height.
55, 53, 54, 58, 60, 61, 62, 56, 57, 52, 51, 63.

Question 3: Following are the earnings (in Rs.) of ten workers:
88, 70, 72, 125, 115, 95, 81, 90, 95, 90
Calculate

Question 4: The Marks obtained by the students in the subject of English are given below.

Find:

\( (i) \; \) Arithmetic mean of their marks by direct and short formula.

\( (ii) \; \) Median of their marks.

Question 5: Given below is a frequency distribution.

Find the mode of the frequency distribution.

Question 6: Ten boys work on a petrol pump station. They get weekly wages as follows:
Wages (in Rs.) 4250, 4350, 4400, 4250, 4350, 4410, 4500, 4300, 4500, 4390.
Find the arithmetic mean by short formula, median and mod of their wages.

Question 7: The arithmetic mean of 45 numbers is 80. Find their sum.

Question 8: Five numbers are 1, 4, 0, 7, 9. Find their mean, median and mode.

Question 9: A set of data contains the values as 148, 145, 160, 157, 156, 160. Show that
Mode>Median>Mean

Question 10: The monthly attendance of 10 students for their lunch in the hostel is recorded as:
21, 15, 16, 18, 14, 17, 15, 12, 13, 11.
Find the median and mode of the attendance. Also find the mean if \(\small{D=A-20}\)

Question 11: On a prize distribution day, 50 students brought pocket money as under:

\( (i) \; \) Find the median and mode of the above data.

\( (ii) \; \) Find the arithmetic mean of the data given above using coding method.

Question 12: The arithmetic mean of the ages of 20 boys is 13 years, 4 months and 5 days. Find the sum of their ages. Of one of the boys is of age exactly 15 years. What is the average age of the ramaining boys?

Question 13: Calculate the arithmetic mean from the following information:

\( (i) \; \) If \(D=X-140\), \(\sum D =500\) and \(n=10\)

\( (ii) \; \) If \(U=\frac{X-130}{6}\), \(\sum U =-150\) and \(n=15\)

\( (iii) \; \) If \(D=x-25\), \(\sum fD =300\) and \(\sum f=20\)

\( (iii) \; \) If \(U=\frac{x-120}{5}\), \(\sum fU =60\) and \(\sum f=100\)

Question 14: The three children Haris, Maham and Minal made the following scores in a game conducted by a group of teachers in the school.

It is decided that the candidate who gets the highest average score will be awarded rupees 1000. Who will get the awarded amount?

Question 15: Given below is a frequency distribution derived by making a substitution as \(\small{D=X-20}\). Calculate the arithmetic mean.

Question 16: Being partners Hafsa and Fatima took part in a quiz programme. They made the following number of points 45, 51, 58, 61, 74, 48, 46, and 50. Compute the average number of points using deviation \(\small{D=x-58}\).

Question 17: A person purchased the following food items:

What is the weighted mean of cost of food items per kg?

Question 18: For the following data, find the weighted mean.

Question 19: A company is planning its next year marketing budget across five years: yearly budgets (in million) are: 5, 7, 8, 6, 7. Find the average budget for the next year.

Question 20: Ahmad obtained the following marks in a certain examination. Find the weighted mean if weights 5, 4, 2, 3, 2, 4 respectively are allowed to the subjects.