Question

[Tu Anh Duong]

Tinh nhanh:

a) 3/10 . (-5/9+3/5) - 3/10 . (3/9+(-2/5)

Answer 1

[Huỳnh Châu Giang]

\(\frac{3}{10}.\left(-\frac{5}{9}+\frac{3}{5}\right)-\frac{3}{10}.\left(\frac{3}{9}+\frac{-2}{5}\right)\)

=\(\frac{3}{10}.\frac{2}{45}-\frac{3}{10}.\left(-\frac{1}{15}\right)\)

\(=\frac{3}{10}.\left(\frac{2}{45}-\left(-\frac{1}{15}\right)\right)\)

\(=\frac{3}{10}.\frac{1}{9}=\frac{1}{30}\)

Answer 2

[Tuyet Trinh Le]

=