# Add 2 5 And 3 7

Add: (i) (-2)/5 and 3/7 (ii) (-5/6) and 4/9 (iii) -3 and 2/3 (iv) (-5/9) and 7/18 (v) ( … viii) 13/(-16) and (-11)/24 (ix)…

(i) (-2)/5 and 3/7

= (-2 × 7)/(5 × 7) + (3 × 5)/(7 × 5)   (∵   LCM of  5 and 7 = 35)

= (-14)/35 + 15/35

= (-14 + 15)/35 = 1/35

(ii) (-5)/6 and 4/9 = (-5/6) + 4/9

= (-5 × 6)/(6 × 6) + (4 × 4)/(9 × 4)   (∵ L.C.M.  of 6 and 9 = 36)

= (-30)/36 + 16/36

= (-30 + 16)/36 = (-14)/36)

(iii) -3 and 2/3 = (-3)/1 + 2/3

= (-3 × 3)/(1 × 3) + (2 × 1)/(3 × 1)     (∵  L.C.M. of  1 and 3 = 3)

= (-9)/3 + 2/3

= (-9 + 2)/3 = (-7)/3

(iv) (-5)/9 and 7/18

= (-5)/9 + 7/18

= (-5 × 2)/(9 × 2) + (7 × 1)/(18 × 1)     (∵ L.C.M. of 9 and 18 = 18)

= (-10)/18 + 7/18 = (-10 + 7)/18 = (-3/18)

(v) -7/24 and (-5)/48

= (-7 × 2)/(24 × 2) + (-5 × 1)/(48 × 1)      (∵ L.C.M. of 24 and 48 = 48)

= (-14)/48 + (-5)/48

= {(-14) + (-5)}/48

= (- 14 – 5)/48

= (-19)/48

(vi) 1/(-18) and 5/(-27)

= (-1/18) + (-5/27)

= (-1 × 3)/(18 × 3) + (-5 × 2)/(27 × 2)     (∵  L.C.M. of 18 and 27 = 54)

= (-3)/54 + (-10)/54

= {(-3) + (-10)}/54

= {(-3) – 10}/54

= (-13)/54

(vii) (-9)/25 and 1/(-75)

= (-9)/25 + (-1)/75

= (-9 × 3)/(25 × 3) + {(-1) × 1}/(75 × 1)      (∵   L.C.M. of  25 and 75 = 75)

= (-27)/75 + (-1)/75

= {(-27) + (-1)}/75

= (- 27 – 1)/75

= (-28)/75

(viii) 13/(-16) and (-11)24 = (-13)/16 + (-11)/24

= (-13 × 3)/(16 × 3) + (-11 × 2)/(24 × 2)     (∵ L.C.M.  of 16 and 24 = 48)

= (-39)/48 + (-22)/48

= {(-39) + (-22)}/48

= (- 39 – 22)/48

= (-61)/48

(ix) -(9/16)  and (-11)/8

= 9/16 + (-11)/8

= (9 × 1)/(16 × 1) + (-11 × 2)/(8 × 2)       (∵ L.C.M.  of 16 and 8 = 16)

= 9/16 + (-22)/16

= {9 + (-22)}/16

= (9 – 22)/16

= (-13)/16