tính nhanh   18.(19191919/21212121 + 88888/99999)

Tinh nhanh:

a, 1/2+1/4+1/8+1/16+1/32+1/64+1/128

b,18-(19191919 / 21212121+ 88888/ 99999)

TÍNH:

\(\dfrac{27}{10}+\dfrac{291}{100}+\dfrac{38}{100}+\dfrac{547}{1000}\dfrac{893}{10000}\)

TÍNH NHANH

a, \(\dfrac{2006\times2005-1}{2004\times2006+2005}\)\

b, \(18\times\left(\dfrac{19191919+88888}{21212121+99999}\right)\)

Tính tHUẬN TIỆN :

63*(19191919 +88888)

21212121+99999

hAI DAU CỘNG GỘP THÀNH 1 NHA

1. Tính:

a. 3/7 + 1/7 x 4/5 - 1

b. (3/20 + 1/2 - 1/15) x 12/49

    ______________________

             7/2 + 2/9

c. 18 x (19191919/21212121 + 88888/99999)

2. Tìm x, biết:

a. 3/5 : x - 4/5 x 3/2 = 1/2

b. 1- (X x 0,5 + X : 4 x 3) : 0,25 = 0,2

Tính nhanh :\(\left(3-\frac{1}{18}\cdot\right)\cdot\left(3-\frac{2}{18}\right)\cdot\left(3-\frac{3}{18}\right)\cdot\cdot\cdot\cdot\left(3-\frac{2019}{18}\right)\)

Tính: A=\(\left(\frac{6}{8}+1\right)\cdot\left(\frac{6}{18}+1\right)\cdot\left(\frac{6}{30}+1\right)\cdot...\cdot\left(\frac{6}{10700}+1\right)\)

Tìm x:

\(\frac{\left(13\frac{2}{9}-15\frac{2}{3}\right)\cdot\left(30^2-5^4\right)}{\left(18\frac{3}{7}-17\frac{1}{4}\right)\cdot\left(25-12\cdot5^2\right)}\cdot x=\frac{\frac{2}{11}+\frac{3}{13}+\frac{4}{15}+\frac{5}{17}}{4\frac{1}{11}+\frac{5}{13}+\frac{9}{15}+\frac{13}{17}}\)

Tính :

\(3,6\cdot31\frac{2}{5}+43,9\cdot\left(10-3\frac{3}{3}\right)-12,5\cdot\left(8-1:\frac{5}{18}\right)=???\)