作业帮SAT MATH QUESTION 1） The sum of eleven different integers is zero.What is the least number of these integers that must be positive?2) In a certain game,each token has one of three possible values:1 point,5points or 10points.How many different combi
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SAT MATH QUESTION 1） The sum of eleven different integers is zero.What is the least number of these integers that must be positive?2) In a certain game,each token has one of three possible values:1 point,5points or 10points.How many different combi
SAT MATH QUESTION
1） The sum of eleven different integers is zero.What is the least number of these integers that must be positive?
2) In a certain game,each token has one of three possible values:1 point,5points or 10points.How many different combinations of these token values are worth a total of 17 points?
SAT MATH QUESTION 1） The sum of eleven different integers is zero.What is the least number of these integers that must be positive?2) In a certain game,each token has one of three possible values:1 point,5points or 10points.How many different combi
1) 1
example:-10,-9,-8,-7,-6,-5,-4,-3,-2,-1,55
2) 6
all 1's,three 5's+two 1's,two 5's+seven 1's,one 5+twelve 1's,one 5+one 10+two 1's,one 10+seven 1's
1) 答案是只需一个，且题目有无数解。
问题问最少有多少个有理数为正数，那么如果需要和为0的话，正有理数和要等于负有理数的和的绝对值，那么便一定要有一个正有理数。我们知道，有理数相加，还是一个有理数，所以任何10个负有理数相加，都可以找出一个正有理数，使绝对值相等。那么解题的话，随便选10个负有理数，取一个正有理数就可以得出来了。
2）第二题我看只能用枚举法，因为有无限个token...
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1) 答案是只需一个，且题目有无数解。
问题问最少有多少个有理数为正数，那么如果需要和为0的话，正有理数和要等于负有理数的和的绝对值，那么便一定要有一个正有理数。我们知道，有理数相加，还是一个有理数，所以任何10个负有理数相加，都可以找出一个正有理数，使绝对值相等。那么解题的话，随便选10个负有理数，取一个正有理数就可以得出来了。
2）第二题我看只能用枚举法，因为有无限个token, 不能用排列组合。解法就如一楼一样，一个一个试，有规律地试也就画30秒，在数学SAT中足够时间了。
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