S.chand publication New Learning Composite mathematics solution of class 7 Chapter 3 Rational numbers Exercise 3B

 Exercise 3B

Question 1

Compare. Write <,> or = in the boxes to make a true statement.

(a) $\frac{-7}{24}$ ____ $\frac{-3}{8}$

Sol :

-7×8 and -3×24

-56 > -72

 $\frac{-7}{24}>\frac{-3}{8}$

(b) $\frac{-1}{5}$ ____ $\frac{-1}{3}$

Sol :

-1×3 and -1×5

-3 > -5

$-\frac{1}{5} > \frac{-1}{3}$

(c) $\frac{6}{10}$ ____ $\frac{1}{35}$

Sol :

6×35 and 1×10

210>10

$\frac{6}{10}>\frac{1}{35}$

(d) $-1\frac{5}{12}$ ____ $-1 \frac{7}{18}$

Sol :

$\frac{-17}{12}\text{ and }\frac{-25}{18}$

-306 < -300

$-1\frac{5}{12}< 1\frac{7}{18}$

(e) $\frac{8}{14}$ ____ $\frac{11}{21}$

Sol :

$\frac{8}{14} \text{ and } \frac{11}{21}$

168>154

$\frac{8}{14}> \frac{11}{21}$

(f) $-1\frac{1}{2}$ _____ $-1\frac{7}{9}$

Sol :

$\frac{-3}{2} \text{ and } \frac{-16}{9}$

-27 > -32

$-1\frac{1}{2} > -1 \frac{7}{9}$

(g) $\frac{-4}{7}$ ____ $\frac{-2}{3}$

Sol :

$\frac{-4}{7} \text{ and } \frac{-2}{5}$

-20 < -14

$-\frac{4}{7} < \frac{2}{5}$

(h) $\frac{9}{20}$ ____ 0.45

Sol :

$\frac{9}{20} \text{ and } \frac{45}{100}$

$\frac{9}{20}=0.45$

(i) -4.5 ____ $3\frac{7}{25}$

Sol :

$-\frac{45}{10} \text{and } \frac{82}{25}$

-225<164

$-45 < 3\frac{7}{25}$

Question 2

Write in order from least to greatest.

(a) $\frac{1}{2}, \frac{-3}{2}, \frac{5}{2}, \frac{-7}{2} , \frac{-2}{2}$

Sol :

$\frac{-7}{2}, \frac{-3}{2}, \frac{-2}{2}, \frac{1}{2},\frac{5}{2}$

(b) $1\frac{1}{2},0, -2\frac{3}{4} ,1 \frac{5}{6}, -1.5$

Sol :

$\frac{3}{2}, 0, \frac{-11}{4}, \frac{11}{6}, -\frac{3}{2}$

$\frac{18}{12},0, \frac{-33}{12}, \frac{22}{12}, \frac{-18}{12}$

$-2\frac{3}{4}, -1.5, 0, 1\frac{1}{2}, 1\frac{5}{6}$

(c) $\frac{1}{4}, \frac{4}{5}, 0, \frac{-7}{10}, -0.8$

Sol :

$\frac{5}{20}, \frac{16}{20}, 0, \frac{-14}{20}, \frac{-16}{20}$

$-0.8, \frac{-7}{10},0, \frac{1}{4}, \frac{4}{5}$

(d) $\frac{-7}{24}, \frac{3}{8}, \frac{-5}{12}, 1\frac{2}{3}, -1\frac{7}{8}$

Sol :

$\frac{-7}{24}, \frac{3}{8}, \frac{-5}{12}, \frac{5}{3}, -\frac{28}{18}$

$\frac{-21}{72}, \frac{27}{72},\frac{-30}{72}, \frac{120}{72},\frac{-100}{72}$

$-1\frac{7}{18}, \frac{-5}{12}, \frac{-7}{24}, \frac{3}{8}, \frac{2}{3}$