Areas Quiz Set 005

The radius of the circle is 12/2 = 6 m. So its area = π × 6 × 6 = 36π sq. m. The left area is $12^2 - 36$π = $144 - 36$π sq. m.

Let L = 13x and B = 6x. We are given 2 × (13x + 6x) = 266, which gives x = 7. So area = L × B = (13 × 7) × (6 × 7) = 3822 sq. meters.

If x% and y% is the increase in the dimensions, then the area of a rectangle increases by $(x + y + {xy}/100)$% = $(4 + 1 + {4 × 1}/100)$% = ${126/25}$, which is same as: $5{1/25}$%

Area of a square is L² = 484, which gives L = 22. If three sides have to be fenced, the required length = 3 × L = 3 × 22 = 66 m.

The area to be plastered is $(2 × l × h) + (2 × b × h) + (l × b)$ = (2 × 8 × 36) + (2 × 2 × 36) + (8 × 2) = 736 sq. m. The cost = 736 × 0.50 = Rs. 368.