9/20 - 8/15 * 5/12=9/20-40/180
=81/180-40/180
=41/180
9/20-8/15x5/12
=9/20-2/9
=41/180
t i c k mk nha bạn
9/20 - 8/15 x 5/12 = 9/20 - 2/9
= 41/180
\(\frac{9}{20}-\frac{8}{15}.\frac{5}{12}=\frac{9}{20}-\frac{2}{9}=\frac{41}{180}\)
9/20 - 8/15 x 5/12 = 9/20 - 2/9 = 41/180
9/20 - 8/15 x 5/12
= 9/20 - 2/9
= 41/180