General Mathematics Paper 2,Nov/Dec. 2010  
Questions: 1 2 3 4 5 6 7 8 9 10 11 12 13 Main
General Comments
Question 1

(a) Two children shared an amount of money in the ratio 3/4 : 2/5. If the smaller share was GH¢25.00, how much was shared between them?
(b) A box contains 5 red, 3 green and 4 blue balls of the same size. If a boy picks two balls from the box one after the other without replacement, what is the probability that both balls are red?


Majority of the candidates were able to find the sum of the ratios correctly but forming the equation to find the amount shared posed a problem to some of them. Some others were not able to identify the smaller ratio. Working with fractions also posed some problems for some of the candidates.
Candidates were expected to convert the fraction to whole numbers by multiplying by their LCM which was 20 to obtain the ratio 15 :8. Hence sum of ratio is 23. If the amount shared between them was y, then 8/23y = GH¢ 25.00. Thus, Y = GH¢23/8 x 25 = GH¢ 71.88                                                                                                
In part (b) Majority of the candidates performed well in this question however, a few of them interpreted the question as sum of probability instead of product of probability. They were able to obtain the probability of the first being red as 5/12 and the second being red as 4/11. Therefore, the probability of both red = 5/12 x 4/11= 5/33.

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