Area Problems
The cost of papering the four walls of a room is Rs. 48. Each one of length, breadth and height of another room is double that of this room.The cost of papering the walls of the new room is?
Let the length, breadth and height of the room be l, b and h respectively As per question Cost of 2(l + b) x h = Rs. 48 ? Required cost = cost of 2 (2l + 2b) x 2h= cost of 4 [2(l + b) x h ]= 4 x Rs. 48= Rs. 192
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.
Cross section area = 1/2 x ( a + b ) x d where a and b are the parallel sides, d is the perpendicular distance between them.? 1/2 x ( a + b ) x d = 640? d = (640 x 2) / 16 = 80m
Diagonal of square = ?2a [a = side]4?2 = ?2 a a = 4 cmNow, area of square = a2 = (42) = 16Side of a square whose area is 2 x 16.a12 = 32 ? a1 = ?32 ?a14?2Now, diagonal of new square = ?2a = ?2x 4 ?2 = 8 cm
EXAMIANS