中二數,inequalities(10PTS)
2007-03-27 7:26 am
7) For two consecutive multiples of 5, the smaller number is greater than half of the larger one.Find the least values of these two numbers.
回答 (3)
2007-03-27 7:55 am
✔ 最佳答案
Let y be the smaller number ,then ( y + 5 ) is the larger one. ( 因為那兩個數是連續的五的倍數 )
y > ( y + 5 ) / 2
2y > y + 5
y > 5
The least value of y is 10 . ( 因為那符號是"大於"而不是"大於or等於" , 同時 y 是五的倍數 )
Therefore , the least values of these two numbers are 10 and 15 .
2007-04-19 8:35 am
唔錯唔錯...明白了
2007-03-27 7:50 am
Let the smaller number be 5x
Then the larger number is 5x+5
We have,
5x > (5x+5)/2
10x > 5x + 5
5x > 5
x > 1
Least possible x is 2
Therefore, least possible values are 10 and 15.
Then the larger number is 5x+5
We have,
5x > (5x+5)/2
10x > 5x + 5
5x > 5
x > 1
Least possible x is 2
Therefore, least possible values are 10 and 15.
收錄日期: 2021-04-12 18:49:46
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https://hk.answers.yahoo.com/question/index?qid=20070326000051KK05456