Free Data Handling 02 Practice Test - 7th grade 

Question 1

If you toss a 5 rupees coin in the air, which of the outcomes has high probability of occuring?

A.

Head

B.

Tail

C.

Head and tail have equal probability.  

D.

Coin will land on its edge every time  

SOLUTION

Solution : C

The probability of getting a head or a tail while tossing a coin is 12 that is equal for both the cases.

Question 2

You have to select the players for your football team. Which of the following given data sets will help you to take the decision?

Data set 1. Name of the players

Data set 2. Height of the players

Data set 3. Stamina of players

Data set 4. Nationality of the players

A.

1 & 2    

B.

2 & 3  

C.

1, 3 & 4   

D.

All the data sets 

SOLUTION

Solution : B

The performance of a football player doesn't depend on his name or nationality. Performance solely depends on  stamina and height. So, the data sets which will help us take a better decision are height and stamina of the players

Question 3

Which of the following data sets are organised?

Data set 1571218252834677898Data set 2101967669564944352311Data set 328546532111325433
A.

Sets 1 and 2  

B.

Sets 2 and 3 

C.

Sets 1 and 3 

D. None of the above

SOLUTION

Solution : A

Data set 1 is in ascending order, whereas data set 2 is in descending order. So, both of them are organized. But we can see that data set 3 is random. Hence, it is an unorganised data set.

Question 4

You have to buy a pair of running shoes. You have 3 brands: Ruma, Peebok and Abibas. You go online and search for reviews of different brands. There you saw that on the basis of stars, brands are rated. More stars imply better rating. Which brand has the highest average rating?

A.

Ruma  

B.

Peebok 

C.

Abibas

D.

Both Abibas and Ruma have the same rating.  

SOLUTION

Solution : C

Average star rating = Total number of stars given by peopleTotal number of people who gave the rating.

For Ruma,average star rating = 180×5+104×4+95×3+12×2+11×1180+104+95+12+11 = 4.07

For Peebok,average star rating = 150×5+110×4+87×3+22×2+23×1150+110+87+22+23 = 3.87

For Abibas,average star rating = 234×5+98×4+88×3+16×2+18×1234+98+88+16+18 = 4.13

4.13 > 4.07 > 3.87

So, Abibas has the highest rating.

Question 5

Find the median of following data set.
12, 6, 87, 9, 54, 23, 43, 19, 56, 34, 69, 74 

A. 38.5
B. 39.5
C. 34 and 43
D. 40.5 

SOLUTION

Solution : A

When you arrange the data in ascending order, you get:

 6          9          12        19        23        34        43        54        56        69        74        87

If number of observations is odd then median is the  (n2)th term

If it is even then median is the mean of the  (n2)th and (n2)+1) th term.

Here the number of observations is 12 - even,

Therefore, the median will be an average of 6th and 7th observation.

 So, Median = 34 + 432 = 772 = 38.5.

Question 6

The bar graph  shown below gives the number of goals scored by a football player AJU. Find the difference between the range and mean of the goals scored by AJU in these 5 matches.

A.

1.6

B.

0.6

C.

2.4  

D.

3.0 

SOLUTION

Solution : B

Mean=Sum of all observationsTotal number of observations​​

Mean = 2+4+3+1+25 = 125 = 2.4

Range = highest observation - lowest observation

Range = 4  1 = 3

Difference between range and mean
             =32.4=0.6

Question 7

The mode of the data set given below is 13. Find the missing observation.

5          ?          6          34        13        1          9          13        9         19        45

A. 9
B. 13
C. 6
D. 34

SOLUTION

Solution : B

1 occurs once
5 occurs once
6 occurs once
9 occurs twice
13 occurs twice
19 occurs once
34 occurs once
45 occurs once

We know that t
he mode of a set of observations is the observation that occurs most often.

Since 9 and 13 both occur twice, they both have the possibility of being modes.

But, the mode of the dataset is given to be 13, which means that 13 has to occur more number of times than 9.

So, the missing number is 13.

Question 8

You throw two dice together and noted the sum of the digits of both the dice. What is the probability of getting 13 as the sum?


___

SOLUTION

Solution :

The largest sum that can obtain from both the dice is 12 (i.e. 6 + 6) when both dice shows 6. So, 13 (as the sum of both the dice) is impossible to occur.Hence,its probability is 0.

Question 9

Mean, median and mode are also known as the measures of __ of a data set.  

SOLUTION

Solution :

A measure of central tendency is a single value that attempts to describe a set of data by identifying the central position within that set of data. The mean, median and mode are all valid measures of central tendency, but under different conditions, some measures of central tendency become more appropriate to use than others. 

Question 10

The range of a data set is either less than or equal to its mean. State whether true or false.

A.

True

B.

False

SOLUTION

Solution : B

Range can be greater than, less than or equal to the mean.

For e.g.:

1. Data Set = {2,10}

Range = 8
Mean = 6
Here, range is greater than mean.

2. Data Set = {3,9}

Range = 6
Mean = 6
Here, range is equal to mean.

3. Data Set ={3,5}

Range = 2
Mean = 4
Here, range is less than mean.