Paper 2 · Mensuration
The diagram shows a swimming pool of uniform cross-section ABCDEF, of length 50 m and breadth 40 m. AB = 50 m, BC = 3,5 m, DC = FE = 20 m, AF = 1,5 m and angles BAF, AFE, BCD and ABC are each 90 degrees. (a) Calculate (i) the cross-sectional area ABCDEF, (ii) the capacity of the swimming pool, giving your answer in kilolitres, (iii) the length of DE. (b) The vertical walls of the pool are to be painted. Given that 7 litres of paint is needed to cover 10 m^2 of wall surface and that the paint is sold in 5 litre tins at a cost of $27 000 per tin. Calculate (i) the total area to be painted, (ii) the number of tins of paint to be bought, (iii) the amount of money needed to buy the paint.
Model answer
125 m^2
Also accepted: 125 m2, 125, 5000 kilolitres, 5 000 kilolitres, 5000, 5 000, 5000 kl, 5 000 000 litres, 5000 m^3, 10,2 m, 10.2 m, 10,2, 10.2, sqrt(104) m, 10,198 m, 450 m^2, 450 m2, 450, 63 tins, 63, $1 701 000, $1701000, 1701000, 1 701 000, 125 m^2; 5000 kilolitres; 10,2 m; 450 m^2; 63 tins; $1 701 000
ZIMSEC Mathematics 4028/2, June 2010, Q11, via the Topical Collection