Bài giải:

S.AMN = $\frac{2}{3}$ x S.NAB = $\frac{2}{3}$x$\frac{1}{3}$ x S.ABC = $\frac{2}{9}$ x S.ABC = 60 ( cm²)

S.BMQ = $\frac{1}{2}$x S.MBC = $\frac{1}{2}$x$\frac{1}{3}$x S.ABC = $\frac{1}{6}$ x S.ABC = 45 (cm²)

S.CPQ = $\frac{1}{2}$x S.PBC = $\frac{1}{2}$x$\frac{1}{3}$x S.ABC = $\frac{1}{6}$ x S.ABC = 45 (cm²)

S.MNPQ = 270 – 60 – 45 – 45 = 120 (cm²)

    Đáp số: 120cm²