Free Data Handling 02 Practice Test - 7th grade 

The probability of getting a head or a tail while tossing a coin is $\frac{1}{2}$ that is equal for both the cases.

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

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.

Average star rating = $\frac{\text{Total number of stars given by people}}{\text{Total number of people who gave the rating}}$.

For Ruma,average star rating = $\frac{180\times 5+104\times 4+95\times 3+12\times 2+11\times 1}{180+104+95+12+11}$ = 4.07

For Peebok,average star rating = $\frac{150\times 5+110\times 4+87\times 3+22\times 2+23\times 1}{150+110+87+22+23}$ = 3.87

For Abibas,average star rating = $\frac{234\times 5+98\times 4+88\times 3+16\times 2+18\times 1}{234+98+88+16+18}$ = 4.13

4.13 > 4.07 > 3.87

So, Abibas has the highest rating.

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  $\left(\frac{n}{2}\right)$th term

If it is even then median is the mean of the  $\left(\frac{n}{2}\right)$th and ($\frac{n}{2})+1)$ th term.

Here the number of observations is 12 - even,

Therefore, the median will be an average of $6^{th}$ and $7^{th}$ observation.

 So, Median=$\frac{34+43}{2}$=$\frac{77}{2}$=38.5.

$Mean=\frac{Sumofallobservations}{Totalnumberofobservations}$​​

$Mean=\frac{2+4+3+1+2}{5}=\frac{12}{5}=$2.4

$\text{Range = highest observation - lowest observation}$

$Range=4-1=$3

$\text{Difference between range and mean}$
             $=3-2.4=0.6$

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.

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.

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. 

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.