Toán Lớp 5: tính nhanh a,9/17 x 6/11 x 52/3 x 121 x 5/22 b, 3 2/15 x 2/9 x 2 16/19 : 9 2/5 x 9 1/2 : 2/3

TRẢ LỜI

1. a)9/17 × 6/11 × 52/3 × 121 × 5/22

   = (9/17 × 52/3) × (6/11 × 121) × 5/22

   = 156/17 × (66 × 5/22)

   = 156/17 × 15

   = 2304/17

   b) 3 2/15 × 2/9 × 2 16/19 : 9 2/5 × 9 1/2 : 2/3

   = 47/15 × 2/9 × 54/19 : 47/5 × 19/2 : 2/3

   = 47/15 × 2/9 × 54/19 × 5/47 × 19/2 × 3/2

   =( 47/15 × 5/47) × (2/9 × 3/2) × (54/19 × 19/2)

   = 1/5 × 1/3 × 27

   = 9/5

    

    

   Trả lời
2. Giải đáp+bước giải:

    a,$\frac{9}{17}$×$\frac{6}{11}$×$\frac{52}{3}$×121×$\frac{5}{22}$ 

   =($\frac{9}{17}$×$\frac{52}{3}$)×($\frac{6}{11}$×121)×$\frac{5}{22}$ 

   =$\frac{156}{17}$×(66×$\frac{5}{22}$ )

   =$\frac{156}{17}$×15

   =$\frac{2304}{17}$

    

   b,3$\frac{2}{15}$×$\frac{2}{9}$×2$\frac{16}{19}$÷9$\frac{2}{5}$×9$\frac{1}{2}$÷$\frac{2}{3}$

   =$\frac{47}{15}$×$\frac{2}{9}$×$\frac{54}{19}$÷$\frac{47}{5}$×$\frac{19}{2}$÷$\frac{2}{3}$

   =$\frac{47}{15}$×$\frac{2}{9}$×$\frac{54}{19}$×$\frac{5}{47}$×$\frac{19}{2}$×$\frac{3}{2}$

   =($\frac{47}{15}$×$\frac{5}{47}$)×($\frac{2}{9}$×$\frac{3}{2}$)×($\frac{54}{19}$×$\frac{19}{2}$)

   =$\frac{1}{5}$×$\frac{1}{3}$×27

   =$\frac{9}{5}$

   Trả lời