Area Problems
A rectangle has 15 cm as its length and 150 cm 2 as its area .Its area is increased to 1 1 / 3 times the original area by increasing only its length . Its new perimeter is?
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
Circumference = No.of revolutions * Distance covered Distance to be covered in 1 min. = (66 X1000)/60 m = 1100 m.Circumference of the wheel = 2 x (22/7) x 0.70 m = 4.4 m.Number of revolutions per min. =(1100/4.4) = 250.