InterviewSolution
Saved Bookmarks
| 1. |
Two concentric circle forming a path which needs to be color at the rate of Rs 7/100 cm2.What is the total cost of painting the path if the diameter of the two circles are 16 cm and 24 cm?1). Rs. 15.02). Rs. 17.63). Rs. 19.24). Rs. 20.8 |
|
Answer» As the shown in the figure, PAINTING needs to be done in the space between two circles Radius of the inner circle (r1) = 16/2 = 8 cm Radius of the OUTER circle (r2) = 24/2 = 12 cm Area of the PAINTED part = π(r2)2 - π(r1)2 = π[(r2)2 - (r1)2] ⇒ Area = $(\frac{{22}}{7}\; \times \;\left( {{{12}^2} - {8^2}} \right))$ ⇒ Area = 22/7 (144 – 64) ⇒ Area = 22/7 × 80 ⇒ Area = 251.4286 cm2 ⇒ For 100 cm2 Price is Rs. 7 ∴ For 251.4286 cm2, price = (251.4286 × 7)/100 = Rs. 17.6 |
|