Find the sum of the lengths of the bases of a trapezium whose area is 4.2 m

Given:

Area of the trapezium $=4.2 \mathrm{~m}^{2}$

Height $=280 \mathrm{~cm}=\frac{280}{100} \mathrm{~m}=2.8 \mathrm{~m}$

Area of trapezium $=\frac{1}{2} \times($ Sum of the parallel bases $) \times($ Height $)$

$4.2=\frac{1}{2} \times($ Sum of the parallel bases $) \times 2.8$

$4.2 \times 2=$ (Sum of the parallel bases) $\times 2.8$

Sum of the parallel bases $=\frac{8.4}{2.8}=3 \mathrm{~m}$