Question

Tính bằng cách hợp lý

53x74-53x7^2+5^2x47

Answer 1

\(=53\cdot\left(74-49\right)+25\cdot47\)

\(=25\cdot53+25\cdot47\)

\(=25\cdot100=2500\)

Answer 2

\(53.74-53.7^2+5^2.47\)

\(=53.74-53.49+25.47\)

\(=53\left(74-49\right)+25.47\)

\(=53.25+25.47\)

\(=25\left(53+47\right)=25.100=2500\)