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26. Donna has three types of coins:$1coins,$2coins and $5coins.the number of $1coins is three times that of $2coins.The number of $2 is 5 more than $5coins.The tatol value of Donna's coins is $325.How many $2coins does she have? 27. A load of 77kg is distributed among Alex,Ben and Curtis,so that Alex... 顯示更多 26. Donna has three types of coins:$1coins,$2coins and $5coins.the number of $1coins is three times that of $2coins.The number of $2 is 5 more than $5coins.The tatol value of Donna's coins is $325.How many $2coins does she have? 27. A load of 77kg is distributed among Alex,Ben and Curtis,so that Alex carries 1over3 of what Ben carries,and Ben carries twice as much as Curtis.What is the weight of the load that Ben carries? 更新: 要齊ALL steps..no skip steps

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26 Donna has three types of coins; $1 coins,$2 coins and $5 coins. The number of $1 coins is three times that of $2 coins. The number of $2 coins is 5 more than the number of $5 coins. The total value of Donna's coins is $325. How many $2 coins does she have? 設她有 $5 有x個 則 $2 有x+5個 $1 有 3(x+5) 依題意 5x + 2(x+5) + 3(x+5) = 325 5x + 2x+10 + 3x+15 = 325 10x = 300 x = 30 所以 $5有30個 $2有30 + 5 = 35個 $1有 3*35 = 105個 (27) Assume that Curtis carry 3x kg, then Ben carries twice as much as curtis, which is 6x kg Alex carries 1/3 of what ben carries, which is 2x... therefore 3x + 6x + 2x = 77kg 11 x = 77kg x = 7kg Ben carries 6x, which is 42 kg

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