DIRECTIONS for the question: Solve the following question and mark the best possible option.
A square plot of ground is surrounded by a gravel path of 10 ft wide, the outside boundary of the gravel path also forming a square. It is desired that the width of the path be doubled, and it is found thattimes as much area covered by gravel is required for the extension as for the original path. What is the area of the plot?
A)
900 sq.ft
B)
1225 sq.ft
C)
1600 sq.ft
D)
1849 sq.ft
E)
2116 sq.ft
C
Let the side of the square plot of ground = a ft. then that of the outer square will be (a+20)ft. and that of the outermost square is (a+40) ft.
The given relation is 7/5 [ (a+20)2 - a2] = (a+40)2 - (a+20)2
so a = 40 and hence area of the plot is 1600 sq.ft.
times as much area covered by gravel is required for the extension as for the original path. What is the area of the plot?
