Ответы и объяснения

  • uyrasik
  • почетный грамотей
2013-04-08T11:14:33+04:00

1. а) 678 / 906 = 113/ 151          б) 3745/ 4445 = 107/127

 

2. - 3 ( х - 2) + 4 ( 1 + 2х) = 10.3 + 20 х

    -3х + 6 + 4 + 8х = 10.3 + 20х

     -3х + 8х - 20х = 10.3 - 6 - 4

     -15х = 0.3

     -х = 0.3 : 15

     х = - 0.02

 

3. 4.8  * ( 2 1/3 - 3 3/8) + 2 4/9

     2 1/3 - 3 3/8 =  7/3 - 27/8 = 56/24 - 81/24 = - 25/24 = - 1 1/24

      4.8  * - 1 1/24 = 4 2/5 * -1 1/24 = 22/5 * - 25/24 = - 550/120 = - 4 7/12

      - 4 7/12 + 2 4/9 = - 55/12 + 22/9 = - 165/ 36 + 88/36 = - 77/36 = - 2 5/36