Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
(1-1/2)×(1-1/3)×(1-1/4)×(1-1/5)×1-1/6=1/2×2/3×3/4×4/5×5/6=1/6
\(a,\left(\dfrac{31}{35}-\dfrac{4}{7}\right)\times\dfrac{8}{7}:2\\ =\left(\dfrac{31}{35}-\dfrac{4\times5}{35}\right)\times\dfrac{8}{7}:2\\ =\dfrac{11}{35}\times\dfrac{8}{7}:2\\ =\dfrac{88}{245}:2\\ =\dfrac{44}{245}\\ b,\left(1-\dfrac{1}{2}\right)\times\left(1-\dfrac{1}{3}\right)\times\left(1-\dfrac{1}{4}\right)\times\left(1-\dfrac{1}{5}\right)\\ =\left(\dfrac{2-1}{2}\right)\times\left(\dfrac{3-1}{3}\right)\times\left(\dfrac{4-1}{4}\right)\times\left(\dfrac{5-1}{5}\right)\\ =\dfrac{1}{2}\times\dfrac{2}{3}\times\dfrac{3}{4}\times\dfrac{4}{5}\\ =\dfrac{1}{3}\times\dfrac{3}{4}\times\dfrac{4}{5}\\ =\dfrac{1}{4}\times\dfrac{4}{5}=\dfrac{1}{5}\)
a, ( \(\dfrac{31}{35}\) - \(\dfrac{4}{7}\)) \(\times\) \(\dfrac{8}{7}\): 2
= \(\left(\dfrac{31}{35}-\dfrac{20}{35}\right)\) \(\times\) \(\dfrac{8}{7}\) : 2
= \(\dfrac{11}{35}\) \(\times\) \(\dfrac{8}{7}\) \(\times\) \(\dfrac{1}{2}\)
= \(\dfrac{44}{35}\) \(\times\) \(\dfrac{4}{7}\)
= \(\dfrac{44}{245}\)
b, ( 1 - \(\dfrac{1}{2}\)) \(\times\) ( 1 - \(\dfrac{1}{3}\)) \(\times\) ( 1 - \(\dfrac{1}{4}\)) \(\times\) ( 1 - \(\dfrac{1}{5}\))
= \(\dfrac{1}{2}\) \(\times\) \(\dfrac{2}{3}\) \(\times\) \(\dfrac{3}{4}\) \(\times\) \(\dfrac{4}{5}\)
= \(\dfrac{1}{5}\) \(\times\) \(\dfrac{2\times3\times4}{2\times3\times4}\)
= \(\dfrac{1}{5}\)
\(A=\dfrac{3}{2}\times\dfrac{4}{3}\times\dfrac{5}{4}\times\dfrac{4}{5}\times\dfrac{5}{6}\)
\(A=\dfrac{7}{2}\)
\(A=\dfrac{3}{2}\times\dfrac{4}{3}\times\dfrac{5}{4}\times\dfrac{6}{5}\times\dfrac{7}{6}\\ A=\dfrac{7}{2}\)
\(x\) \(\times\) \(\dfrac{1}{2}\) = 1 - \(\dfrac{1}{3}\)
\(x\) \(\times\)\(\dfrac{1}{2}\) = \(\dfrac{2}{3}\)
\(x\) = \(\dfrac{2}{3}\) : \(\dfrac{1}{2}\)
\(x\) = \(\dfrac{4}{3}\)
mk ko viết đề nha:
a)=(1/2+1/2)+ (1/3+2/3)+(1/4 +3/4)+(1/5+4/5)
=(2/2 + 3/3) + (4/4 + 5/5)
=2/2 + 4/2
=6/4
À mik lm đc câu a thui nha!Nhưng k cho mik vs nhé!
= 51/20
----------------------------------
= 3/14
------------------------------------
= 4/7 - 2/7
= 2/7
--------------------------------------
= 17/45
---------------------------------------
= 2/3
--------------------------------------
= 2 x 1/4
= 1/2
1/2+2/3 = 3/3 = 1
x : 2/5 = 5/6
x = 5/6x2/5
x = 1/3
\(\dfrac{1}{2}+\dfrac{2}{3}=\dfrac{3}{3}=1\)
x : \(\dfrac{2}{5}\) = \(\dfrac{5}{6}\)
x = \(\dfrac{5}{6}\)x\(\dfrac{2}{5}\)
x = \(\dfrac{1}{3}\)