$a) 30 – 4.(12 + 15)$ $b) 126 – (-4) + 7 – 20$ $c) 8. 12 – 8. 5$

0 bình luận về “$a) 30 – 4.(12 + 15)$ $b) 126 – (-4) + 7 – 20$ $c) 8. 12 – 8. 5$”

1. a) 30 – 4 (12 + 15)

   = 30 – 4.27

   = 30 – 108

   = -78

   b) 126 – (-4) + 7 – 20

   = 126 + 4 + 7 – 20

   = 137 – 20

   = 117

   c) 8.12 – 8.5

   = 8.(12 – 5)

   = 8 . 7

   = 56

    

   Trả lời

2. a. 30-4.(12+15)

   = 30 – 108

   = -78

   b. 126 – ( -4) + 7 – 20

   = 130 + 7 – 20

   = 117

   c. 8.12-8.5

   = 96 – 40

   = 56

   Trả lời