ML AGGARWAL CLASS 7 Chapter 17 Data Handling Exercise 17.2

 

  Exercise 17.2

Question 1

(i)Mean $=\frac{40+30+30+0+26+60}{6}$

$\begin{aligned} &=\frac{186}{6} \\ \text { Mean } &=31 \end{aligned}$

(ii) Mean $=\frac{3+5+7+9+11+13+15}{7}$

= 9

Question 2

Means of first five whole number 

$=\frac{0+1+2+3+4}{5}$

$=\frac{10}{5}$

= 2

Question 3

Mean $=\frac{36+35+50+46+60+55}{6}$

Mean $=47$

Question 4

The mean Enrollment of the school for the period = $\frac{1555+1670+1750+2013+2540+2825}{6}$

Mean = 2058.834

Question 5

(i) Highest marks obtained by the students = 95

Lowest marks obtained by the student = 39

(ii)Range of the mark = Maximum - minimum marks

=95-39

= 56

(iii)Mean marks obtained by the students = $=\frac{85+76+90+85+39+ 48+56+

95+81+75 }{10}$

= 73

Question 6

(i)Height of the tallest girl = 151cm

(ii)Height of the shortest girl=128cm

(iii)Mean height of the girls =  $=\frac{35+ 150+139+ 128+ 151+132+146+ 149+143+141}{10}$

141.4

(iv)5 girls 

Question 7

Arithmetic means = $\frac{8+4+6+x+2+7}{6}=5$

=$\frac{27+x}{6}=5$

$x=30-27$

$x=3$

Question 8

Means = $\frac{\Sigma f_{i} x_{i}}{\Sigma f_{i}}$

(diagram to be added)

Means = $\frac{2(2)+3(2)+4(6)+7(7)+10(2)}{3+2+6+7+2}$

$=\frac{6+6+24+49+20}{20}$

$=\frac{105}{20}$

Means = 5.25