题目内容
已知:| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
分析:由
=
=
,可得a=3k,b=4k,c=5k,然后将其代入a+b+c=24,即可求得a、b、c的值.
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
解答:解:法(1):∵
=
=
,
∴
=
=
=
,(5分)
即
=
=
=
,(2分)
解得:a=6,b=8,c=10(3分).
解法(2):设
=
=
=k,
则a=3k,b=4k,c=5k(5分).
代入a+b+c=24,得3k+4k+5k=24,(2分)
解得:a=6,b=8,c=10(3分).
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
∴
| a+b+c |
| 3+4+5 |
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
即
| 24 |
| 3+4+5 |
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
解得:a=6,b=8,c=10(3分).
解法(2):设
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
则a=3k,b=4k,c=5k(5分).
代入a+b+c=24,得3k+4k+5k=24,(2分)
解得:a=6,b=8,c=10(3分).
点评:此题考查了比例的性质.此题难度不大,解题的关键是注意比例的性质与设
=
=
=k的解题方法.
| a |
| 3 |
| b |
| 4 |
| c |
| 5 |
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