Tính nhanh : \(\frac{1}{8}\div12,5\%+\left(\frac{1\times2\times3+6\times4\times2}{5\times3\times1+5\times15\times25}+\frac{1}{2}\div50\%\right)-\left(\frac{1}{16}\div6,25\%+\frac{3+2+1+2+4+6}{1+3+5+25+15+5}\right)-\frac{1}{4}\div25\%\)

tính tổng :\(B=\frac{5}{1\times2}+\frac{13}{2\times3}+\frac{25}{3\times4}+\frac{41}{4\times5}+...+\frac{181}{9\times10}\)

( Bài hơi dài , mong mọi người giúp ạ ! )

\(\text{Tính P :}\)

\(P=\frac{0,8:\left(\frac{4}{5}\times1,25\right)}{0,64-\frac{1}{25}}+\frac{\left(1,08-\frac{2}{25}\right):\frac{4}{7}}{\left(6\frac{5}{9}-3\frac{1}{4}\right)\times2\frac{2}{17}}+\left(1,2\times0,5\right):\frac{4}{5}\)

Bài 1:

a) (-0,25) . 0,45 . 0,4 . (-0,125) . 0,55 . (-8)

b) [ 20,83 . 0,2 + (-9,17 . 0,2) ] : [ 2,47 . 0,5 - (-3,53 . 0,5) ]

c) \(\frac{(9\frac{3}{4}\div5,2+3,4\times2\frac{7}{34})\div(-1\frac{9}{16})}{\left(-0,31\right).8\frac{2}{5}-5,61\div\left(-27\frac{1}{2}\right)}\)

Tính nhanh:\(\frac{1+2}{1\times2}+\frac{1+2+3}{1\times2\times3}+...+\frac{1+2+...+999}{1\times2\times...\times999}+\frac{1+2+...+999+1000}{1\times2\times...\times999\times1000}\)

Tính nhanh:\(\frac{1\times2}{1+2}+\frac{1\times2\times3}{1+2+3}+..+\frac{1\times2\times...\times999}{1+2+...+999}+\frac{1\times2\times...\times999\times1000}{1+2+...+999+1000}\)

cho A=\(\frac{1,1+0,19-1,3\times2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2\)

B=\(\left(5\frac{7}{8}-2\frac{1}{2}-0,5\right):2\frac{23}{26}\)

a. Rút gọn A

b. Tim x \(\in\)Z để A<x<B

\(A=\frac{1,11+0,19-1,3\times2}{2,06+0,54}-(\frac{1}{2}+\frac{1}{3}):2\)

\(B=(5\frac{7}{8}-2\frac{1}{4}-0,5):2\frac{23}{26}\)

a. Rút gọn A và B

b. Tìm x\(\in\)Z để A<x<B

Tính:

\(\frac{0,8\div\left(\frac{4}{5}\times1,25\right)}{0,64-\frac{1}{25}}+\frac{\left(1,08-\frac{2}{5}\right)\div\frac{4}{7}}{\left(6\frac{5}{9}-3\frac{1}{4}\right)\times2\frac{2}{17}}+\left(1,2\times0,5\right)\div\frac{4}{5}\)

giúp mình với nhé mn, nhanh nha mình cần gấp