\(\text{ Tính bằng cách thuận tiện nhất rồi viết kết quả dưới dạng số thập phân :}\)

\(\text{Trả lời : }\)

\(\frac{42\text{ x }37}{74\text{ x }84}=\frac{42\text{ x }37}{37\text{ x }2\text{ x }42\text{ x }2}=\frac{1}{4}\)

\(\text{Chúc bạn học tốt ! }\)

=123x10=1230

\(=123\times\left(6+3+1\right)\)
\(=123\times10\)
\(=1230\)

\(123\times6+123+3\times123\\ =123\times\left(6+1+3\right)\\ =123\times10\\ =1230\)

`123 xx 137 - 123 xx 36 - 123`

`= 123 xx 137-123xx36-123xx1`

`=123xx(137-36-1)`

`=123xx100`

`=12300`

$#flo2k9$

`123 xx 137 - 123 xx 36 - 123`

= `123 xx ( 137 - 36 - 1 )`

= `123 xx 100`

= `12300`

\(123\times137-123\times36-123=123\times\left(137-36-1\right)=123\times100=12300\)

123 x 54 + 123 x 46

= 123 x (54 +46) = 123 x 100

= 12300

 123 x 45 x 55 x 123 = 123 x ( 45 + 55 )

                               = 123 x       100

                               =           12300

có sai đề bài k?

 123 x 45 x 55 x 123 = 123 x ( 45 x 55 )

                                 = 304425

( 1×2×3×......×9×10 ) × ( 218 × 37 - 109×74)

= ( 1×2×3×......×9×10 ) × ( 8066 - 8066)

= ( 1×2×3×......×9×10 ) × 0

= 0

\(\left(1\times2\times3\times...\times9\times10\right)\times\left(218\times37-109\times74\right)=\) 

\(=\left(1\times2\times3\times...\times9\times10\right)\times\left(8066-8066\right)\) 

\(=\left(1\times2\times3\times...\times9\times10\right)\times0\) 

\(=0\)

\(=\left(1\cdot2\cdot3\cdot...\cdot10\right)\cdot\left[37\cdot109\left(2-2\right)\right]=0\)

\(\frac{37}{35}:\frac{5}{4}:\frac{74}{25}\)

\(=\frac{37}{35}:\left(\frac{5}{4}\times\frac{74}{25}\right)\)

\(=\frac{37}{35}:\frac{37}{10}\)

\(=\frac{2}{7}\)

\(\frac{37}{35}:\frac{5}{4}:\frac{74}{25}\)

=\(\frac{37}{35}x\frac{4}{5}x\frac{25}{74}\)

\(=\left(\frac{37}{35}x\frac{25}{74}\right)x\frac{4}{5}\)

\(=\frac{1}{7}x\frac{5}{2}x\frac{4}{5}\)

\(=\frac{1x5x2x2}{7x2x5}\)

\(=\frac{2}{7}\)

\(\frac{37}{35}:\frac{5}{4}:\frac{74}{25}\)

\(=\frac{37}{35}:\frac{74}{25}:\frac{5}{4}\)

\(=\frac{37}{35}\times\frac{25}{74}\times\frac{4}{5}\)

\(=\frac{37\times25\times4}{35\times74\times5}\)

\(=\frac{37\times5\times5\times2\times2}{5\times7\times37\times2\times5}\)

\(=\frac{2}{7}\)

~ Thiên Mã ~