小学三年级怎样解甲,乙,丙三人今年的年龄和是49岁甲的年龄是丙的2倍丙比甲小9? 甲、乙、丙三人,甲的年龄比乙的年龄的2倍还大3岁,乙的年龄比...
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\u5219\u4e59\uff1d49-12-24=13\u5c81
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\uff08a-b)=-(b-a)
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a-b-c=a-(b+c\uff09
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甲的年龄是丙的2倍,丙比甲小9岁,所以可以得出丙今年9,甲今年18岁,则乙的年龄是49-18-9=22岁。根据甲丙两人的年龄关系,可以先用“差倍问题”的方法求出甲丙两人的年龄。
差=9,倍数=2
较小数(丙的岁数)=差÷(倍数-1)
=9÷(2-1)
=9(岁)
甲的岁数=9x2=18(岁)
乙的岁数=49-18-9=22(岁)
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绛旓細鐢诧細48+24+10-7-10=65(鏈)涔锛48+7+9-24-5=35(鏈)涓锛48+10+5-10-9=44(鏈)
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绛旓細瑙: 鐢层佷笝95鍑忓幓涔欍佷笝锛95-92=3 璇存槑鐢叉瘮涔欏3浜,鎵 浠(87-3)/2=42(浜)鏄 涔欑彮浜烘暟銆87-42=45(浜)鏄敳鐝汉鏁般92-42=50(浜)鏄笝鐝汉鏁般傜瓟: 鐢茬彮45浜,涔鐝42 浜,涓鐝50浜恒
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