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?
Head
Tail
Head and tail have equal probability.
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
1 & 2
2 & 3
1, 3 & 4
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 328546532111325433Sets 1 and 2
Sets 2 and 3
Sets 1 and 3
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?
Ruma
Peebok
Abibas
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 > 3.87So, 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
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.
1.6
0.6
2.4
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 observationRange = 4 − 1 = 3
Difference between range and mean
=3−2.4=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
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 the 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
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.
True
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.