" (ii) "(4)/(7)+0+(-13)/(7)+(-8)/(9)+(17)/(21)

Using commutativity and associativity of addition of rational numbers,express each of the following as a rational number: (2)/(5)+(8)/(3)+(-11)/(15)+(4)/(5)+(-2)/(3) (ii) (4)/(7)+0+(-8)/(9)+(-13)/(7)+(17)/(21)

Evaluate : (iii) (4)/(7)+0+(-8)/(9)+(-13)/(7)+(17)/(9)

Evaluate : (iii) (4)/(7)-(-8)/(9)-(13)/(7)+(17)/(9)

Re-arrange suitably and find the sum in each of the following: (3)/(5)+(7)/(3)+(9)/(5)+(-13)/(15)+(-7)/(3) (ii) (4)/(13)+(-5)/(8)+(-8)/(13)+(9)/(13)

Simplify: ((4)/(7)+(-8)/(9) +(-5)/(21) +(1)/(3)) .

Write the following as mixed fractions. (7)/(2), (8)/(5), (9)/(4), (13)/(5), (17)/(3)

(-4)/(7)+(2)/(9)+(-5)/(4)+(8)/(21)

Using commutativity and associativity of addition of rational numbers, express each of the following as a rational number: 2/5+8/3+(-11)/(15)+4/5+(-2)/3 (ii) 4/7+\ 0+(-8)/9+(-13)/7+(17)/(21)

Which of the following are in descending order of their values? (5)/(9),(7)/(11),(8)/(15),(11)/(17) (b) (5)/(9),(8)/(15),(11)/(17),(7)/(11) (c) (11)/(17),(7)/(11),(5)/(15),(5)/(9)(d)(11)/(17),(7)/(11),(5)/(9),(8)/(15)