Length of three sides of a triangular field are 15 m, 19 m and 22 m respectively. What is the area of the field? (correct to one decimal place)

140.2 m²

For our triangle:

a=15

b=19

c=22

First, we calculate the semi-perimeter:

S = (15+19+22)/2 = 28

Now we apply Heron's formula:

Area = \(\sqrt {s(s - a)(s - b)(s - c)}\)

= \(\sqrt {28(28 - 15)(28 - 19)(28 - 22)}\)

= \(\sqrt {19656}\)

Area = 140.2m²