Question

find the cost of fencing a rectangular park of sides 60m and 45m respectively at rate of 20 per meter

Answer 1

perimeter =2*(l+b)=2*(60+45)=210m
rate is 20 rupees per meter so cost is 210*20=4200 rupees
as fencing is done throughout the boundary of the field we find out the perimeter

Answer 2

perimeter of rectangle =2(l+b)
                                     =2(60+45)
                                     =2(105)
                                     =210m^2
so,the cost for per meter is 20
=210*20
=4200