tính a) 5/6+7/12-2/9 b) 4/9×5/8+1/6 c) 2: 3/11-13/12

2 bình luận về “tính a) 5/6+7/12-2/9 b) 4/9×5/8+1/6 c) 2: 3/11-13/12”

1. color{green}{#Thucute2008!}

   Tính :

   a) 5/6 + 7/12 – 2/9 = 10/12 + 7/12 – 2//9 = 17/12 – 2/9 = 51/36 – 8/36 = 43/36

   b) 4/9 × 5/8 + 1/6 = 1/9 × 5/2 + 1/6 = 5/18 + 1/6 = 5/18 + 3/18 = 8/18 = 4/9

   c) 2 : 3/11 – 13/12 = 2 × 11/3 – 13/12 = 22/3 – 13/12 = 88/12 – 1312 = 75/12

   Trả lời
2. Giải đáp:

    a)

   5/6+7/12-2/9 (MSC=36)

   =30/36+21/36-8/36

   =\frac{30+21-8}{36}

   =43/36

    b)

   4/9xx 5/8+ 1/6

   =\frac{4xx5}{9xx4xx2}+1/6

   =5/18+1/6

   =5/18+3/18

   =8/18

   =4/9

   c)

   2: 3/11-13/12

   =2xx 11/3-13/12

   =22/3-13/12

   =88/12-13/12

   =75/12

   =25/4

   Trả lời