Find length and cost ?

Question

A rectangular plot of land is 50 m wide . The cost of fencing the plot at the rate of Rs 18 per metre is Rs 4680 . Find

The length of the plot

The cost of leveling the plot at the rate of Rs 7.6 per m^2

Answer 1

Let length of land be x.
Thus, perimeter of land = 50m + 50m + x + x = 100m + 2x

Cost of fencing land is Rs 18 per meter, so cost of fencing land will be
= (100 + 2x) * 18
= 1800 + 36x

The actual cost is Rs 4680, so we have:

4680 = 1800 + 36x
36x = 4680 - 1800
36x = 2880
x = 2880 / 36
x = 80

Thus, length of land is 80m.

Area of land
= length * width
= 80m * 50m
= 4000m^2

Cost of leveling plot
= Rs7.6 * 4000
= Rs 30400