Class 7 Maths

Data Handling NCERT Exercise 3.3

Question 6: Take the data giving the minimum and the maximum temperature of various cities given in the beginning of this Chapter. Plot a double bar graph using the data and answer the following:

Temperature of Cities
(as on 20/06/2006
CityMaxMin
Ahmadabad38°C29°C
Amritsar37°C26°C
Bangalore28°C21°C
Chennai36°C27°
Delhi38°C28°C
Jaipur39°C29°C
Jammu41°C26°C
Mumbai32°C27°C

Answer:

bar graph

(a) Which city has the largest difference in the minimum and maximum temperature on the given date?

Answer: Jammu

(b) Which is the hottest city and which is the coldest city?

Answer: Jammu is the hottest city and Bangalore is the coldest city.

(c) Name two cities where maximum temperature of one was less than the minimum temperature of the other.

Answer: Maximum temperature of Bangalore is less than the minimum temperature of Ahmadabad and Jaipur.

(d) Name the city which has the least difference between its minimum and the maximum temperature.

Answer: Mumbai

Exercise 3.4

Question 1: Tell whether the following is certain to happen, impossible, can happen but not certain.

(a) You are older today than yesterday.

Answer: Certain to happen

(b) A tossed coin will land heads up.

Answer: Can happen but not certain.

(c) A die when tossed shall land with 8 on top.

Answer: Impossible

(d) The next traffic light seen will be green.

Answer: Can happen but not certain.

(e) Tomorrow will be a cloudy day.

Answer: Can happen but not certain.

Question 2: There are 6 marbles in a box with numbers from 1 to 6 marked on each of them.

(a) What is the probability of drawing a marble with number 2?

Answer: Number of marbles with 2 written on it = 1

Total number of marbles = 6

Probability of drawing a marble with number 2 `= 1/6`

(b) What is the probability of drawing a marble with number 5?

Answer: Number of marbles with 5 written on it = 1

Total number of marbles = 6

Probability of drawing a marble with number 5 `= 1/6`

Question 3: A coin is flipped to decide which team starts the game. What is the probability that your team will start?

Answer: Number of head or tail in a toss of coin = 1
Total number of events = 2 (one for head and one for tail)
Probability of getting either a head or a tail `= 1/2`