\(\frac{15-\frac{15}{7}-\frac{15}{2}}{3-\frac{3}{7}-\frac{3}{12}}\)

\(=\frac{15.\left(1-\frac{1}{7}-\frac{1}{12}\right)}{3.\left(1-\frac{1}{7}-\frac{1}{12}\right)}=\frac{15}{3}\)

Dấu " . " là nhân nhé !!!

\(\frac{15-\frac{15}{7}-\frac{15}{12}}{3-\frac{3}{7}-\frac{3}{12}}\)

= \(\frac{15.\left(1-\frac{1}{7}-\frac{1}{12}\right)}{3.\left(1-\frac{1}{7}-\frac{1}{12}\right)}\)

= \(\frac{15}{3}\)

= 5

=  15/3

=5

15-\(\frac{15}{7}\)-\(\frac{15}{12}\)

3-\(\frac{3}{7}\)-\(\frac{3}{12}\)

=15.[1-\(\frac{1}{7}\)-\(\frac{1}{12}\)]

3.[1-\(\frac{1}{7}\)-\(\frac{1}{12}\)]

=\(\frac{15}{3}\)=5

3/10 + 4/12 + 2/10 + 2/12

= ( 3/10 + 2/10 ) + ( 4/12 + 2/12) 

= 5/10 + 6/12

= 1/2 + 1/2 

= 2/2 = 1 

10/15 -7/5 * 10/15 - 5/5

= 10/15 * ( 7/5 -5/5)

= 2/3 * 2/5 

= 4/15 

Cbht!!!

3/10+4/12+2/10+2/12

=(3/10+2/10)+(4/12+2/12)

=1/2+1/2

=1

= 4/3 x ( 15/7 - 8/7)

= 4/3 x 7/7

= 4/3 x 1

= 4/3

4/3×15/7 - 4/3×8/7

=4/3 × ( 15/7 - 8/7 )

=4/3 × 1

=4/3

Hok tốt

\(\frac{4}{3}.\frac{15}{7}-\frac{4}{3}.\frac{8}{7}\)

\(=\frac{4}{3}\left(\frac{15}{7}-\frac{8}{7}\right)\)

\(=\frac{4}{3}.1=\frac{4}{3}\)

\(15-\frac{15}{7}-\frac{15}{12}=11\frac{17}{28}\)

\(=\frac{325}{28}\)

\(3-\frac{3}{7}-\frac{3}{13}=2\frac{31}{91}\)

\(=\frac{213}{91}\)

làm từng bước bạn ơi !

\(\frac{12}{15}\)+  \(\frac{4}{5}\)= \(\frac{8}{5}\)