Question

Ai cứu ạ

Answer 1

\(\left(1,1+1,2+...+1,9\right)\times\left(123,5-24,7\times5\right)\\ =\left(1,1+1,2+...+1,9\right)\times\left(123,5-123,5\right)\\ =\left(1,1+1,2+...+1,9\right)\times0\\ =0\)

Answer 2

\(=\left(1.1+1.2+...+1.9\right)\cdot\left(123.5-123.5\right)=0\)