Question

 

Tính nhanh 8/15 : 2/11 + 7/15 : 2/11

 

Answer 1

=(8/15+7/15):2/11

=1:2/11

=11/2

Answer 2

\(\frac{8}{15}:\frac{2}{11}+\frac{7}{15}:\frac{2}{11}\)

\(=\frac{8}{15}\times\frac{11}{2}+\frac{7}{15}\times\frac{11}{2}\)

\(=\frac{11}{2}\times\left(\frac{8}{15}+\frac{7}{15}\right)\)

\(=\frac{11}{2}\times1\)

\(=\frac{11}{2}\)

P/s tham khảo nha