(列識）
18.The length of a wire is 360 cm . If it is divided into 3 portions in the ration of 1 : 3 : 8 , find the length of the longest portion .
5. The population of a town was 5000000 which included 87500 newborn babies . What was the birth rate in birth rate in births per 1000 people ?
Maths Question
2007-04-09 10:24 pm
回答 (1)
2007-04-09 10:33 pm
✔ 最佳答案
Let x be the shortest length of the wire x+3x+8x = 360cm
12x = 360cm
x= 30cm
so the length of the longest portion = 8*30cm =240cm
birth rate in births per 1000 people =(87,500 / 5,000,000) * 1000 = 17.5 people
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