a)1,3.2 . 1/4 – 1, 3.3 1/4 Câu 2:tìm x: a)1/4:x=2,4-4/5 b)2x-(0,5+ 2/3):2 1/3=0,25

2 bình luận về “a)1,3.2 . 1/4 – 1, 3.3 1/4 Câu 2:tìm x: a)1/4:x=2,4-4/5 b)2x-(0,5+ 2/3):2 1/3=0,25”

1. câu 2a)$\\$$\frac{1}{4}$ : x = 2,4 -$\frac{4}{5}$ $\\$$\frac{1}{4}$ : x =$\frac{8}{5}$ $\\$ x =$\frac{1}{4}$ :$\frac{8}{5}$ $\\$x= $\frac{5}{32}$ vậy x= $\frac{5}{32} b)$$\\$ 2x-(0,5+$\frac{2}{3}$ ):2$\frac{1}{3}$ = 0,25 $\\$2x-$\frac{7}{6}$ :$\frac{7}{3}$ = 0,25 $\\$2x-$\frac{1}{2}$ = 0,25 $\\$2x=0,25+$\frac{1}{2}$ $\\$2x=$\frac{3}{4}$ $\\$x=$\frac{3}{4}$ :2 $\\$x=$\frac{3}{8}$ 

   câu 1 1,3 .2$\frac{1}{4}$ – 1,3 . 3$\frac{1}{4}$ $\\$= 1,3.$\frac{9}{4}$ -1,3 .$\frac{13}{4}$ $\\$ =1,3 . ($\frac{9}{4}$ +$\frac{13}{4}$ ) $\\$ =1,3.(-1) $\\$ =-1,3

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2. 1.

   a)1,3.2 1/4 – 1, 3.3 1/4

   =1,3.9/4-1,3.13/4

   =1,3.(9/4-13/4)

   =1,3.(-1)

   =-1,3

   2.

   a)1/4:x=2,4-4/5

   1/4:x=8/5

   x = 1/4 : 8/5

   x=1/4 . 5/8

   x=5/32

   Vậyx=5/32

   b)2x-(0,5+ 2/3):2 1/3=0,25

   2x-7/6 : 7/3=0,25

   2x – 7/6.3/7=0,25

   2x-1/2=0,25

   2x=0,25+1/2

   2x=0,25+0,5

   2x=0,75

   x=0,75:2

   x=0,375

   Vậy x=0,375

    

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