AC Lim's answer to Breina's Primary 6 Maths Percentage Singapore question.
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2 methods. Hope this helps
Date Posted:
3 years ago
Nothing is wrong with AC Lim’s approach. His workings are fully correct.
They started with 2160 stamps. when John gives Leesha 30% of his stamps, there is no change in the number of stamps. When Leesha sold 50% of her stamps, they had 1369 stamps left.
Note that only Leesha sold stamps. John did not sell stamps at all. And there were 891 fewer stamps than before. So, Leesha must have sold 891 stamps.
50% of Leesha’s stamps = 891
100% of Leesha’s stamps = 1782
So, before Leesha sold her stamps, she had 1782 stamps (after receiving stamps from John).
John had 2160 - 1782 = 378 stamps (after giving Leesha the stamps).
Since John did not sell any stamps, he must have had 378 stamps at the end.
They started with 2160 stamps. when John gives Leesha 30% of his stamps, there is no change in the number of stamps. When Leesha sold 50% of her stamps, they had 1369 stamps left.
Note that only Leesha sold stamps. John did not sell stamps at all. And there were 891 fewer stamps than before. So, Leesha must have sold 891 stamps.
50% of Leesha’s stamps = 891
100% of Leesha’s stamps = 1782
So, before Leesha sold her stamps, she had 1782 stamps (after receiving stamps from John).
John had 2160 - 1782 = 378 stamps (after giving Leesha the stamps).
Since John did not sell any stamps, he must have had 378 stamps at the end.
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