Let the parallel sides be 3a and 5a.So Area of trapezium = 1/2 x sum of parallel side x perpendicular distance between them.? 1/2 (3a +5a) x 12 = 384? 8a = 64? a =8? Smaller side = 3x = 3 x 8 = 24 cm.
Perimeter of rectangle = Circumference of circle = 2?r=2 x ( 22/7 ) x 42= 264 cm Now perimeter of rectangle = 2 x ( 6a + 5a )? 2 x (6a + 5a) = 264? a = 12Smaller side of rectangle = 5a = 60 cm
Length = (40 x 10 ) dm = 400 dm.Breadth = (15 x 10 ) dm = 150 dm.Area of veranda = (400 x 150 ) dm2Area of one stone = (6 x 5 ) dm2? Required number of stones = (400 x 150) /(6 x 5) = 2000