Data Handling quiz

The class size of the class intervals 10-20, 20-30, 30-40 is:

The upper limit of the class interval 30-40 is:

The sum of all the central angles in a pie chart is:

The probability of getting a head when a fair coin is tossed once is:

In a histogram, the bars are drawn:

If 25% of the students in a class like Mathematics, the central angle of this sector in a pie chart is:

The probability of getting 7 when an ordinary die is thrown is:

The number of times a particular observation occurs in a data set is called its:

A bag has 3 red and 2 blue balls. The probability of drawing a blue ball at random is:

With classes 20-30 and 30-40, the observation 30 is counted in the class:

Distinguish between raw data and grouped data, giving one example of each. (2 marks)

In a survey of 60 people, 15 prefer tea. Find the central angle of the sector representing tea in a pie chart. (2 marks)

List all the outcomes when a die is thrown once. Which outcomes make up the event "getting an odd number"? (2 marks)

A letter is chosen at random from the letters of the word MATHEMATICS. Find the probability that it is a vowel. (2 marks)

Why is the upper limit of a class interval not included in that class? Explain with an example. (2 marks)

A spinner has 5 equal sectors coloured red, red, green, blue and yellow. Find the probability that it stops on red, and on a colour that is not red. (2 marks)

In a pie chart showing the choices of 500 people, a sector has a central angle of 72 degrees. How many people does this sector represent? (2 marks)

What are equally likely outcomes? Give one example of an experiment with equally likely outcomes and one without. (2 marks)

Cards numbered 1 to 20 are mixed and one is drawn at random. Find the probability that the number on the card is a multiple of 5. (2 marks)

Data ranging from 0 to 40 is to be grouped into classes of size 5. Write the first three class intervals and the total number of classes. (2 marks)

The modes of transport of 120 students are: bus 40, walking 30, bicycle 20 and car 30. Find the central angle for each mode for drawing a pie chart, and check that their sum is 360 degrees. (3 marks)

The marks (out of 50) of 25 students are: 12, 25, 37, 8, 19, 44, 31, 22, 15, 39, 5, 28, 47, 33, 18, 26, 41, 9, 35, 21, 14, 30, 42, 27, 36. Prepare a grouped frequency distribution with classes 0-10, 10-20, 20-30, 30-40 and 40-50. How many students scored 30 or more? (3 marks)

A box contains 5 red, 8 white and 7 black marbles. One marble is taken out at random. Find the probability that it is (i) red (ii) white (iii) not black. (3 marks)

A pie chart shows how a family spends its monthly income of Rs 36,000. The central angles are: food 120 degrees, rent 90 degrees, education 60 degrees, savings 40 degrees and others 50 degrees. Find the amount spent on food, on education and the amount saved. (3 marks)

Two coins are tossed together. List all the outcomes and find the probability of getting (i) exactly one head (ii) at least one head (iii) no head. (3 marks)

Read the passage and answer the questions. A survey of 40 students of Class 8 recorded the hours they spend watching television daily: 0-1 hour: 6 students, 1-2 hours: 14, 2-3 hours: 12, 3-4 hours: 6, 4-5 hours: 2. (i) How many students watch television for less than 2 hours a day? (ii) Which class interval has the maximum number of students? (iii) What percentage of students watch television for 3 hours or more? (5 marks)

Read the passage and answer the questions. In a school council election, 720 votes were cast for three candidates P, Q and R. The result was shown in a pie chart in which the central angles were 120 degrees for P, 150 degrees for Q and 90 degrees for R. (i) Find the number of votes received by each candidate. (ii) Who won the election and by how many votes over the next candidate? (iii) What fraction of the total votes did R receive? (5 marks)

Read the passage and answer the questions. For a lucky draw at a school fair, 100 tickets numbered 1 to 100 are put in a box and one ticket is drawn at random. (i) Find the probability that the number on the ticket is even. (ii) Find the probability that it is a multiple of 10. (iii) Find the probability that it is divisible by 7. (5 marks)

Read the passage and answer the questions. Weather records of a city show that it rained on 9 of the 30 days of June last year. (i) Based on these records, what is the chance that it rains on a day in June? (ii) What is the chance that it does not rain on a day in June? (iii) Is this chance found in the same way as the probability of getting a head on tossing a coin? Explain. (5 marks)

Read the passage and answer the questions. A quality inspector at a factory checked a batch of 500 bulbs and found that 20 of them were defective. (i) Find the probability that a bulb chosen at random from the batch is defective. (ii) Find the probability that it is not defective. (iii) If a shopkeeper picks 50 bulbs at random from a similar batch, about how many would you expect to be defective? (5 marks)

The daily wages of 50 workers are: Rs 300-350: 8 workers, Rs 350-400: 12, Rs 400-450: 15, Rs 450-500: 10, Rs 500-550: 5. Draw a histogram for this data. From it find (i) the number of workers earning Rs 450 or more (ii) the percentage of workers earning less than Rs 400 (iii) the class with the maximum number of workers. (6 marks)

The languages spoken at home by 72 students are: Hindi 30, English 12, Tamil 18 and Bengali 12. Explain the steps for drawing a pie chart, calculate the central angles and draw the pie chart with labels. Which language is spoken by exactly one-fourth of the students? (6 marks)

Explain the terms random experiment, outcome, event and equally likely outcomes with the help of throwing a die. Draw a spinner with 6 equal sectors coloured blue, blue, blue, red, red and green, and find the probability of the pointer stopping on blue, on red, on green and on a colour other than green. (6 marks)

The ages (in years) of 30 people in a housing society are: 3, 15, 27, 42, 8, 33, 56, 61, 19, 24, 37, 45, 12, 50, 68, 29, 5, 40, 22, 35, 58, 17, 31, 48, 26, 64, 10, 39, 53, 21. Using tally marks, prepare a grouped frequency distribution with classes 0-15, 15-30, 30-45, 45-60 and 60-75. Draw a histogram and state which age group has the most people. (6 marks)

A die was thrown 60 times and the outcomes were: 1 came 8 times, 2 came 11 times, 3 came 9 times, 4 came 12 times, 5 came 10 times and 6 came 10 times. Draw a bar graph for this data. Find the fraction of throws that gave 4 and compare it with the theoretical probability of getting 4. Explain what you expect to happen to this fraction if the die is thrown 6000 times. (6 marks)