The parallel edges of a trapezium shaped field are 77m and 60m.If the remaining edges are 25M and 26m,what is the total cost of digging twice the land at the rate of Rs.10 persq m and fencing thr land three times at the rate of Rs.20 per m

2 answers

From each of the ends of the 60 m side, draw altitudes to the 77 m side.
You now have a rectangle and two right-angled triangles.
Let the height of all three be h,

for the triangle with hypotenuse 25, let the base be x, then
x^2 + h^2 = 25^2 -----> h^2 = 625 - x^2

for the triangle with hypotenuse 26, let the base be 10-x
h^2 + (10-x)^2 = 26^2 ---> h^2 = 376 - (10-x)^2

625 - x^2 = 376 - (10-x)^2
a bit of simple algebra yields:
x = 49/20 = 2.45 m

now you can find the base of the other triangle , 10-x
and the height h

All is now known, and you can find area, perimeter or whatever else you need.
Ans