作业帮求教一道SAT的数学题：For a dog that weighs w pounds and is x inches long to qualify for a certain competition,the difference between w and 1.5x can be no more than 5.If a dog with length 24 inches qualifies for the competition,what is one po
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求教一道SAT的数学题：For a dog that weighs w pounds and is x inches long to qualify for a certain competition,the difference between w and 1.5x can be no more than 5.If a dog with length 24 inches qualifies for the competition,what is one po
求教一道SAT的数学题：
For a dog that weighs w pounds and is x inches long to qualify for a certain competition,the difference between w and 1.5x can be no more than 5.If a dog with length 24 inches qualifies for the competition,what is one possible weight,in pounds,of this dog?
疑问：我答案求对了,但是我看SAT官方提供的参考答案是31
求教一道SAT的数学题：For a dog that weighs w pounds and is x inches long to qualify for a certain competition,the difference between w and 1.5x can be no more than 5.If a dog with length 24 inches qualifies for the competition,what is one po
difference between w and 1.5x没有说谁是被减数,w-1.5x
狗长24英寸，也就是x=24,1.5x=36。第一句说，参加比赛的狗满足下面的条件：重量w和1.5x的差不能超过5。那就是w-1.5x<=5,且1.5x-w<=5，又1.5x=36。所以w<=41且w>=31
题目只说w和1.5x的差小于等于5，没说哪个大，哪个小，所以可以列两个不等式
w-1.5x≤5 w≤5+1.5x=5+1.5*24=41
1.5x-w≤5 w≥1.5x-5=1.5*24-5=31
∴31≤w≤41