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P AST S CHOOL E XAM SOLUTION (P6) 2

3 Anglo Chinese School (Primary) / P6 Mathematics 2008 / Combined Preliminary Examination / Paper 2

At first a fruit stall, the number of oranges is the same as the number of apples at firs. 6 oranges and 14 apples were sold. As a result, the ratio of the number of oranges to the number of apples became 7 : 5. a) How many apples were left? b) How many fruits were there at first? 4 OrangeApple u5u 7u+6 = 5u+14 7u6 5u14 2u = 8 1u = 4 (a) 5u = 5x4 = 20 (b) 5u+14 = 5x4 +14 = 34 34x2 = 68 Ans: a)20 apples b)68 fruits

5 Singapore Chinese Girls’ School (Primary) / Preliminary Examination 2008 / Q48

At a farm, 40% of the animal are cows, 90% of the remainder are sheep and the rest are ducks. There are 56 more sheep than cows. After some cows died, 20% of the remaining animals at the farm are cows. How many cows are there left at the farm? 6 cowRemainder Sheep Duck (3x9=27u) (3u) (20u) 27u-20u=7u 7u  56 1u  8 Cow: 20u  20x8=160 Sheep: 27u  27x8=216 Duck: 3u  3x8= cowSheepDuck 160-? -? u 4u 4u  = 240 1u  240÷4 = 60 Ans.: 60 cows

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