Bonjour,
23 : 1) 1/5-2
1-10/5
-9/5
-1,8
2) 12/7×14/20
12×2/20
3×2/5
6/5
1,2
3) 2×1/5
2/1×1/5
2×1/1×5
2/5
0,4
24 : 1) 1/2-3/8
4-3/8
1/8
0,125
2) 4×1/3
4/1×1/3
4×1/1×3
4/3
1,33...
3) 6-28/5
30-28/5
2/5
0,4
25 : 1) -1/4+3/2
-1+6/4
5/4
1,25
2) 3/4×8/15-1
3×2/15-1
2/5-1
-3/5.
-0,6
3) 2-4/3
6-4/3
2/3
0,66...
26 : 1)
[tex] \frac{1}{1 + \frac{1}{4} } \\ = \frac{ \frac{1}{5} }{4} \\ = \frac{4}{5} \\ = 0.8[/tex]
2)
[tex]\frac{1}{1 + \frac{1}{1 + \frac{2}{3} } } \\ = \frac{1}{1 + \frac{ \frac{1}{5} }{3} } \\ = \frac{1}{1 + \frac{3}{5} } \\ = \frac{1}{\frac{8}{5}} \\ = \frac{5}{8} \\ = 0.625[/tex]
27 : 1)
[tex]\frac{1}{1 + \frac{3}{2} } \\ = \frac{2}{5} \\ = 0.4[/tex]
2)
[tex] \frac{1}{1 + \frac{1}{1 + \frac{4}{3} } } \\ = \frac{1}{1 + \frac{1}{ \frac{7}{3} }} \\ = \frac{1}{1 + \frac{3}{7} } \\ = \frac{ \frac{1}{10} }{7} \\ = \frac{7}{10} \\ = 0.7[/tex]
