7. a. If the area ratio for two similar rectangular plots is 1/16, what is the ratio of their lengths? (2) b.|f the two rectangles in (5) above have their widths 8cm and xcm . If the area ratio of the two rectangles is 1/4 find the value of x. (2) 8. If two painters take 15 hours to paint a wall. How long will it take 3 painters to paint the same wall? (1) 9. If the wall in (7) above is 547712 nd the area of a wall which three painters take 24 hours to paint. (1) 10. A model of a house is done to a scale of 1:50. Find the actual area of a window with an area of 112.5m'm20n the model. ((1) 11. What is the area on the model of a door opening with an actual area of 3.2m2? (1)