Question 12 Marks
Individual scores of a school cricket eleven in a match are given below:$10, 9, 31, 45, 0, 4, 8, 15, 12, 0, 6.$Find the average score.
Answer$\text { Mean }=\frac{\sum x}{N}$
Average score
$=\frac{10+9+31+45+0+4+8+15+12+0+6}{11}$
$=\frac{140}{11} $
$=12.7 .$
View full question & answer→Question 22 Marks
A boy scored the following marks in various class tests during a terminal exam, each test being marked out of $20.17, 15, 16, 7, 10, 14, 12, 19, 16, 12$ Find his average mean marks.
Answer Mean $=\frac{\sum x}{N}$
Avg. mean marks
$=\frac{17+15+16+7+10+14+12+19+16+12}{10} $
$=\frac{138}{10} $
$=13.8 .$
View full question & answer→Question 32 Marks
The weight of the seven members of a family, in kilograms are given below:$20, 52, 56, 72, 64, 13, 80.$Find mean weight.
AnswerMean $=\frac{\sum x}{N}$
Mean weight
$=\frac{20+52+56+72+64+13+80}{7} $
$=\frac{351}{7} $
$=51 \ kg .$
View full question & answer→Question 42 Marks
Find the median of the following sets of numbers$.15, 8, 14, 20, 13, 12, 16$
Answer$15,8,14,20,13,12,16$
Arranging the data in ascending order,
$8,12,13,14,15,16,20$
Here $N =7$
$\therefore$ Median is $\left(\frac{ N +1}{2}\right)^{\text {th }}$ term
$=\left(\frac{7+1}{2}\right)=4^{\text {th }}$ term
$\therefore$ Median $=14$.
View full question & answer→Question 52 Marks
The mean of $16$ natural numbers is $48.$ Find the resulting mean, if each of the number is multiplied by $4.$
AnswerMean $= 48$
Total numbers $= n = 16$
Therefore,
Resulting mean $($when each number is multiplied by $4)$
$= 48 \times 4$
$= 192.$
View full question & answer→Question 62 Marks
The mean of $16$ natural numbers is $48.$ Find the resulting mean, if each of the number is decreased by $8.$
AnswerMean $= 48$
Total numbers $= n = 16$
Therefore,
Resulting mean $($when each number is decreased by $8)$
$= 48 - 8$
$= 40.$
View full question & answer→Question 72 Marks
The mean of $16$ natural numbers is $48.$ Find the resulting mean, if each of the number is increased by $5.$
AnswerMean $= 48$
Total numbers $= n = 16$
Therefore,
Resulting mean $($when each number is increased by $5)$
$= 48 + 5$
$= 53.$
View full question & answer→Question 82 Marks
For the set of numbers given below, find mean $: 3, 0, 5, 2, 6, 2$
AnswerMean $=\frac{\sum x}{N}$
Mean,
$=\frac{3+0+5+2+6+2}{6} $
$=\frac{(18)}{(6)^{\circ}}$
$=3.$
View full question & answer→Question 92 Marks
For the set of numbers given below, find mean $: 5, 7, 8, 4, 6$
AnswerMean $=\frac{\sum x}{N}$
Mean
$=\frac{5+7+8+4+6}{5} $
$=\frac{30}{5} $
$=6 .$
View full question & answer→Question 102 Marks
A test out of $25$ marks was given to $16$ students and marks scored are recorded below $: 25, 8, 14, 20, 16, 22, 10, 15, 8, 7, 24, 18, 19, 6, 11, 14$ In the report, marks were entered out of $50.$ What is the mean of the recorded marks in the report?
AnswerIf the marks are entered out of $50,$ then the given marks shall be doubled.
So, new marks scored will be $2$ times the marks scored by the $16$ students initially
i.e. $2 \times 240=480 $
Mean marks $=\frac{480}{16}=30$
View full question & answer→Question 112 Marks
A test out of $25$ marks was given to $16$ students and marks scored are recorded below:$25, 8, 14, 20, 16, 22, 10, 15, 8, 7, 24, 18, 19, 6, 11, 14$ Find the mean marks
AnswerMarks scored by the $16$ students
$=25+8+14+20+16+22+10+15+8+7+24+18+19+6+11+14 $
$=240$
Mean marks $=\frac{240}{16}$
$=15$
View full question & answer→Question 122 Marks
Define primary data and secondary data.
AnswerPrimary data is that which is collected by investigator himself through personal observations with a definite plan or design in mind.
Secondary data is that which has been collected previously by someone other
Than the investigator but is used by the investigator for some specific purpose.
View full question & answer→