Question

Determine o valor dos seguintes produtos utilizando o cancelamento sempre que possível 5/8 × 3/10 × 4 b) 3/5 × 15/16 × 8/8 c) 11/4 × 1/5 × 10/ 7 d) 7/3 × 12/7 × 5/8 e) 1/16 × 10/3 × 42/35 × 24/34 f) 35/40 × 8/22 × 44/22 × 30/25 g) 24/36 × 49/63 × 10/6 × 36/25 h) 18/7 × 36/50 × 7/24 × 60/48 i) 23/28 × 4/18 × 7/22 × 4/8 j) 99/99 × 20/48 × 5/34 × 64/30

Answer 1

a) 5/8 x 3/10 x 4 =

   (5/8 x 3/10)                   (5/10 = 1/2 )
      (1/8x3/2)

            3/24 x 4=              (3/24 = 1/8)
             1/8 x 4 = (÷4)
                   1/4

b) 3/5 × 15/16 × 8/8 =
    
   (3/5 x 15/16)              (15/5 = 3/1)

    (3/1 x 3/16) x 8/8 =
       3 x 3/16 x 1 = 9/16   

c)  1/4 × 1/5 × 10/ 7 =
     1/4 x (1/5 x 10/7) =        (10/5 = 2/1)
      1/4 x 2/7 =                      (2/4 = 1/2)
       1/2 x 1/7 = 1/14

d) (7/3 × 12/7) × 5/8 =    (7/7 = 1)
     (1/3 x 12/1) x 5/8 =    (12/3 = 4)
             4 x 5/8 =             (4/8 = 1/2)
               = 5/2
    
e) 1/16 × 10/3 × 42/35 × 24/34 = Como é multiplicação podemos reorganizar os termos agrupando da melhor forma para calcular:

     1/6 x 42/35 x 10/3 x 24/34 =             (42/6 = 7/1)    e    (24/3 = 8/1)
     (1/1 x 7/35) x (10/1 x 8/34) =            (7/35 = 1/5)
           1/5 x 10/1 x 8/34 =                      (10/5 = 2/1)
                 2          x 8/34 =                      (2/34 = 1/17)
                     1/1 x  8/17 = 8/17

f) 35/40 × 8/22 × 44/22 × 30/25 =       (8/40 = 1/5)  e  (44/22 = 2)  e (30/35 = 6/7)
   ( 35/5 x 1/22) x 2 x 6/7 =
       7    x  1/22  x 2 x 6/7 =
           7/22 x 6/7 x 2 =  (÷7)
             6/22 x 2 =         (÷2)
               = 6/11

g) 24/36 × 49/63 × 10/6 × 36/25 =      (24/36 ÷ 6 = 4/6)  (49/63 ÷ 7 = 6/9)
      4/6    x    6/9    x 10/6 x 36/25 =      (4/6 x 6/9) = 4/9
               4/9          x 10/6 x 36/35 =      (36/35 x 10/6 ÷ 6 = 6x10/35)
               4/9        x 60/35 =      ÷3
               4/3       x 20/35  =
                     80/105     ÷5 = 16/21

h) 18/7 × 36/50 × 7/24 × 60/48 =
     18/7 x 7/24 x 36/50 x 60/48 =  (18/7 x 7/24  ÷7 = 18/24  ÷ 6 = 3/8)
           3/8         x 36/50 x 60/48 =  (3/8 x 36/50 ÷ 2 = 3/4 x 18/50)
             3/4 x 18/50 x 60/48 =        (18/50 x 60/48 ÷10 = 18/5 x 6/48)
             3/4 x 18/5 x 6/48 =            (18/5 x 6/48  ÷ 2 = 9/5 x 6/24)
             3/4 x 9/5 x 6/24 =   
             3/4 x 9/5 x 1/4 =       
           (3x9x1)/(4x5x4) = 27/80

i) 3/28 × 4/18 × 7/22 × 4/8 =
   1/7 x 2/9 x 7/22 x 1/2 =  (2/9x1/2 = 1/9)
    1/7 x 7/22 x 1/9 = (1/7 x 7/22 = 1/22)
        1/22 x 1/9 = 1/ 198

j)  99/99 × 20/48 × 5/34 × 64/30 =  (20/48 ÷4 = 5/12) (5/34 x 64/30 = 1/6x64/30)
           1  x  5/12 x  1/6 x 64/30 =  (64/30 ÷2 = 32/15)
                   5/12 x 1/6 x 32/15 =  (5/12 x 32/15 ÷ 5 = 1x32/12x3 = 32/36 = 16/18)
                   1/6 x 16/18 =
                   16/6x48 = 16/288 ÷4 = 4/72 (÷4) = 1/18