9/11 1/9:11/24
a) -9/11 + 1/9 .18/3
b) 16/29 + -13/29 + 4/13 - 16/39
c) 9/24 . 14/25 + 5/24 . 11/25 - 1 và 9/24
d) (-111,82) + 13,3 - 8,18 + 16,7
a: =-9/11+2/3=-27/33+22/33=-5/33
b: =(16/29-13/29)+12/39-16/39
=3/29-4/39=1/1131
d: =(-111,82-8,18)+(13,3+16,7)=-120+30=-90
1,Tính
[(24*47-23) / (24+47+23)] * [(3+3/7-3/11+3/1001-3/13) / (9/1001-9/13+9/7-9/11+9)]
9/11 + 1/12 : 11/24
`9/11 + 1/12 : 11/24 = 9/11 + 1/12 xx 24/11 = 9/11 + 2/11 = 11/11= 1`
9/11 1/12:11/24
9/11 + 1/12 : 11/24
`9/11+1/12:11/24=9/11+1/12xx24/11=9/11+[2xx12]/[12xx11]=9/11+2/11=11/11=1`
Tìm x biết: x* (2015 / 8*9 + 1925 / 9*10 + 1795 / 10*11 + 1629 / 11*12 + 6) = 1/24
Chứng tỏ rằng giá trị các biểu thức là 1 số hữu tỉ A =6/71/2 B = 4/15 nhân -25/24 C =0,3 nhân 12,8+0,3 nhân 7,2 D= 1/10 nhân 11+1/11+12+…+1/99 nhân 100 E =4/11+4/121-4/12321/9/11+9/121-9/12321
tính giá trị biểu thức:
A= 24 . 47 - 23 / 24 + 47 - 23 . (3 + 3 + 3/7 - 3 /11 +3 / 1001 - 3/13) / ( 9/ 1001 - 9 /13 +9/7 - 9/ 11 +9 )
Tính :
2/5 + 11/15 =
7/8 - 7/9 =
11/13 x 26/31 =
16/24 : 4 =
30 : 6/5 =
9/16 : 4 =
1/2 : 1/3 x 8/15 =
\(\dfrac{2}{5}+\dfrac{11}{15}=\dfrac{6}{15}+\dfrac{11}{15}=\dfrac{17}{15}\)
\(\dfrac{7}{8}-\dfrac{7}{9}=\dfrac{63}{72}-\dfrac{56}{72}=\dfrac{7}{72}\)
\(\dfrac{11}{13}\times\dfrac{26}{31}=\dfrac{22}{31}\)
\(\dfrac{16}{24}:4=\dfrac{16}{24}\times\dfrac{1}{4}=\dfrac{4}{24}=\dfrac{1}{6}\)
\(30:\dfrac{6}{5}=30\times\dfrac{5}{6}=25\)
\(\dfrac{9}{16}:4=\dfrac{9}{16}\times\dfrac{1}{4}=\dfrac{9}{64}\)
\(\dfrac{1}{2}:\dfrac{1}{3}\times\dfrac{8}{15}=\dfrac{1}{2}\times3\times\dfrac{8}{15}=\dfrac{4}{5}\)
2/5 + 11/15 = 17/15
7/8 - 7/9 = 7/72
11/13 x 26/31 = 22/31
16/24 : 4 = 1/6
30 : 6/5 = 25
9/16 : 4 = 9/64
1/2 : 1/3 x 8/15 = 3/2 x 8/15 = 4/5