Diện tích mảnh đất là:

48 x 15 = 720 \(\left(m^2\right)\)

Diện tích làm nhà là:

720 x \(\dfrac{1}{6}\) = 120 \(\left(m^2\right)\)

\(\left(\dfrac{1}{2}+\dfrac{4}{7}\right)-\left(\dfrac{3}{7}-\dfrac{3}{10}\right)\)

\(=\dfrac{1}{2}+\dfrac{4}{7}-\dfrac{3}{7}+\dfrac{3}{10}\)

\(=\left(\dfrac{1}{2}+\dfrac{3}{10}\right)+\left(\dfrac{4}{7}-\dfrac{3}{7}\right)\)

\(=\left(\dfrac{5}{10}+\dfrac{3}{10}\right)+\dfrac{1}{7}\)

\(=\dfrac{8}{10}+\dfrac{1}{7}\)

\(=\dfrac{4}{5}+\dfrac{1}{7}\)

\(=\dfrac{28}{35}+\dfrac{5}{35}\)

\(=\dfrac{33}{35}\)