这里有学数学的吗？ Compatible Number 在中国是什么概念？

来源: CirrusCloud 于 2012-09-17 07:07:37 [] [博客] [旧帖] [给我悄悄话] 阅读数 : (2046 bytes)

我看定义很含糊啊。

Compatible Number

Definition of Compatible Number

  • Compatible numbers are numbers that are close in value to the actual numbers and easy to add, subtract, multiply, or divide mentally.
  • They are useful in estimating the sum, difference, product, or quotient.
Examples of Compatible Number
  • Estimate 13 ÷ 3.6.

To estimate the quotient, choose the compatible  numbers 12 and 4 as 12 and 4 are compatible with each other. Also notice that 12 is closer to 13 and 4 is closer to 3.6.

This is my comment: Division like the example above might be obvious, but some of them are not.  For example, 9.4 + 62.6, what are the compatible numbers?  It could be 9 + 61 (because 9 + 1 = 10), it could be 9 + 62 (simply drop decimal) and it could be 10 + 62 (because 10 plus anything is easy) , pending on which way is "easy" to the individual and what reason that is "easy".  Is there a standard answer to this question? 

所有跟帖： 

• thanks, my d is about your kid grade. My experience is estimatio -didadida- ♀ 给 didadida 发送悄悄话 (0 bytes) () 09/17/2012 postreply 07:19:38

• Sorry, your post was cutoff. Would you please re-port? -CirrusCloud- ♀ 给 CirrusCloud 发送悄悄话 CirrusCloud 的博客首页 (0 bytes) () 09/17/2012 postreply 07:24:56

• sorry. My experience was their concepts some of them are differe -didadida- ♀ 给 didadida 发送悄悄话 (53 bytes) () 09/17/2012 postreply 10:29:02

• we have to accept it. -didadida- ♀ 给 didadida 发送悄悄话 (0 bytes) () 09/17/2012 postreply 10:30:57

• 不是学数学的，感觉就是近似数，近似到多少位取决于需要 -xchmm- ♀ 给 xchmm 发送悄悄话 (0 bytes) () 09/17/2012 postreply 07:42:59

• 看题不认真。 你对我最后一段的问题给个答案？ -CirrusCloud- ♀ 给 CirrusCloud 发送悄悄话 CirrusCloud 的博客首页 (0 bytes) () 09/17/2012 postreply 08:20:29

• 我认为没有标准答案，因为目的是帮助简化，方便运算，所以说取决于需要，看需要多close。如果先简化再运算，不会考虑1+9 -xchmm- ♀ 给 xchmm 发送悄悄话 (0 bytes) () 09/17/2012 postreply 08:36:15

• 这题应该是有标准答案的。 因为同时问的是： -CirrusCloud- ♀ 给 CirrusCloud 发送悄悄话 CirrusCloud 的博客首页 (84 bytes) () 09/17/2012 postreply 08:45:17

• 我觉得有合理解释就行 -xchmm- ♀ 给 xchmm 发送悄悄话 (0 bytes) () 09/17/2012 postreply 08:52:07

• the answer is yours is wrong, mine was too. -didadida- ♀ 给 didadida 发送悄悄话 (82 bytes) () 09/17/2012 postreply 10:33:37

• I didn't try to argue -- just wanted to know what the exact -CirrusCloud- ♀ 给 CirrusCloud 发送悄悄话 CirrusCloud 的博客首页 (72 bytes) () 09/17/2012 postreply 10:41:54

• At first, i was just like you. I made my D almost get B-. She di -didadida- ♀ 给 didadida 发送悄悄话 (318 bytes) () 09/17/2012 postreply 13:22:33

• she did solve the problem right at beginning. -didadida- ♀ 给 didadida 发送悄悄话 (0 bytes) () 09/17/2012 postreply 13:24:53

• Appreciate your input. But look, I didn't try to do anything to -CirrusCloud- ♀ 给 CirrusCloud 发送悄悄话 CirrusCloud 的博客首页 (1361 bytes) () 09/17/2012 postreply 15:12:31

请您先登陆，再发跟帖！