SOLUTION:

Question 986280:
Answer by abhimessi(4) (Show Source): You can put this solution on YOUR website!
HEY THERE
GIVEN,PERIMETER OF THE FIELD=400m
LENGTH OF FIELD=26+b
PERIMETER FORMULA=2(L+B)
2(L+B)=400---->L+B=200 26+B+B=200(SINCE LENGTH IS 26+BREADTH)
26+2B=200 2B=174 OR B=87 M
LENGTH=26+87=113M