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Question 1
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(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?
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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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