Tìm x biết: (\(\dfrac{2}{15}\)+\(\dfrac{2}{35}\)+\(\dfrac{2}{63}\)):x= \(\dfrac{1}{18}\)..
Tìm x: x- (\(\dfrac{2+2+2+2 }{3+15+35+63}\))= \(\dfrac{1}{9}\)
Tính nhanh:
\(\dfrac{2}{3}\) + \(\dfrac{2}{15}\) + \(\dfrac{2}{35}\) + \(\dfrac{2}{63}\) + \(\dfrac{2}{99}\) + \(\dfrac{2}{143}\) .
Tìm X
X:3\(\dfrac{1}{15}\)-\(\dfrac{3}{4}\)=2\(\dfrac{1}{4}\)
X nhân 3\(\dfrac{2}{3}\)-1\(\dfrac{2}{3}\)=2\(\dfrac{1}{3}\)
\(a,\dfrac{15-x}{14}=\dfrac{5}{7}\)
\(b,\dfrac{x}{9}=\dfrac{17}{3}\)
\(c,15-\dfrac{x}{2}=\dfrac{3}{7}\)
Tìm x
Tinh nhanh
\(\dfrac{1}{3}+\dfrac{1}{15}+\dfrac{1}{35}+\dfrac{1}{63}+......+\dfrac{1}{483}\)
Giá trị biểu thức:?
\(\dfrac{1}{3}+\dfrac{13}{15}+\dfrac{33}{35}+\dfrac{61}{63}+\dfrac{97}{99}\)
Tính nhanh
a, S= \(\dfrac{1}{3}\) + \(\dfrac{1}{15}\) + \(\dfrac{1}{35}\) + \(\dfrac{1}{63}\) + \(\dfrac{1}{99}\) + \(\dfrac{1}{143}\)
b, A = \(\dfrac{1}{3}\) + \(\dfrac{1}{6}\) + \(\dfrac{1}{10}\) + \(\dfrac{1}{15}\) + \(\dfrac{1}{21}\) + \(\dfrac{1}{28}\)
c, H =\(\dfrac{4047991-2010x2009}{4050000-2011x2009}\)
d, T = \(\dfrac{2009x20010+2000}{2011x2010-2020}\)
e, P = \(\dfrac{7589-80,5x69,3}{7485,05-79x69,3}\)
f, B = 5,1 x 42,2 + 1,7 x 448 x 3 - 0,15 x 700
Giúp mình với
Tìm \(x\):
a)\(x\times\dfrac{4}{5}:2=\dfrac{6}{7}\) b)\(\dfrac{6}{5}:x:\dfrac{5}{4}=\dfrac{10}{15}\)