\(8,4\times111+4,2\times2\times898-8,4\)\(=8,4\times111+8,4\times898-8,4=8,4\times\left(111+898-1\right)=8,4\times1008=8467,2\)

\(\frac{1,4.2012.6+4,2.4024+8,4.976}{1+2+3+4+...+999}\)

\(=\frac{8,4.2012+4,2.2.2012+8,4.976}{1+2+3+4+...+999}\)

\(=\frac{8,4\left(2012+2012+976\right)}{1+2+3+4+...+999}\)

\(=\frac{8,4.5000}{500.999}\)

\(=\frac{84.500}{999.500}\)

\(=\frac{84}{999}\)

\(=\frac{28}{333}\)

(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2.................999 x 2 x 2 x 2 ?

A.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 > 999 x 2 x 2 x 2 = 9990 > 7992

B.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 < 999 x 2 x 2 x 2 = 9990 < 7992

C.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 = 999 x 2 x 2 x 2 = 9990 = 7992

Đáp án A nhé

(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2.................999 x 2 x 2 x 2 ?

A.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 > 999 x 2 x 2 x 2 = 9990 > 7992

B.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 < 999 x 2 x 2 x 2 = 9990 < 7992

C.(111 + 222 + 333 + 444 + 555 + 666 + 777 + 888 + 999)x 2 = 999 x 2 x 2 x 2 = 9990 = 7992

\(A=\frac{\frac{4}{111}+\frac{4}{123}-\frac{4}{999}}{\frac{2}{111}+\frac{2}{123}+\frac{2}{999}}\)

\(=\frac{4.\left(\frac{1}{111}+\frac{1}{123}+\frac{1}{999}\right)}{2.\left(\frac{1}{111}+\frac{1}{123}+\frac{1}{999}\right)}\)

\(=\frac{4}{2}=2\)

a)3254+146+1698=5098

4367+199+501=5067

4400+2148+252=6800

b)921+898+2079=3898

1255+436+145=1836

467+999+9533=10999

a/3254+146+1698=5098   

4367+199+501=5067

4400+2148+252=6800

b/921+898+2079=3898

1255+436+145=1836

467+999+9533=10999

a)3254+146+1698=5098

4367+199+501=5067

4400+2148+252=6800

b)921+898+2079=3898

1255+436+145=1836

467+999+9533=10999

\(\frac{\frac{4}{111}+\frac{4}{123}+\frac{4}{999}}{\frac{2}{111}+\frac{2}{123}+\frac{2}{999}}=\frac{4.\left(\frac{1}{111}+\frac{1}{123}+\frac{1}{999}\right)}{2.\left(\frac{1}{111}+\frac{1}{123}+\frac{1}{999}\right)}=\frac{4}{2}=2\)

\(=\frac{2\left(\frac{2}{111}+\frac{2}{123}+\frac{2}{999}\right)}{\frac{2}{111}+\frac{2}{123}+\frac{2}{999}}\)

\(=2\)

1. 0

2. 4,2

3. -54

\(=\frac{4.\left(\frac{1}{111}+\frac{1}{123}-\frac{1}{999}\right)}{2.\left(\frac{1}{111}+\frac{1}{123}-\frac{1}{999}\right)}=\frac{4}{2}=2\)

Sửa đề lại rồi đó hả bạn?!

\(=\frac{4}{111}:\frac{2}{111}+\frac{4}{123}:\frac{2}{123}-\frac{4}{999}:\frac{2}{999}\)

\(=\frac{4}{111}\times\frac{111}{2}+\frac{4}{123}\times\frac{123}{2}-\frac{4}{999}\times\frac{999}{2}\)

\(=2+2-2\)

\(=2\)

:))