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Heiman

2011-09-13 11:53 pm

1.Mary has 28 $5-coins, some $2-coins and some 50€-coins.If the ratio of the value of $5-coins to that of $2-coins to that of 50€-coins is 35:24:11 , find the ratio of the number of $5-coins to $2-coins to 50€-coins.

2. Sarah has 32 marbles and Cherie has 48 marbles.If Sarah and Cherie each gives the same number of marbles to Sam, the numbers of Sarah and Cherie's marbles will be in the ratio 13:21 . Find the number of marbles that Sarah gives to Sam.

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回答 (1)

myisland8132

2011-09-14 12:08 am

✔ 最佳答案

1 Let there are x $5-coins, y $2-coins and z 50 €-coins

5x : 2y : 0.5z = 35 : 24 : 11

5x = 35k, 2y = 24k and 0.5z = 11k

x = 7k, y = 12k and z = 22k

The ratio of the number of $5-coins to $2-coins to 50€-coins

7 : 12 : 22

2 Let Sarah give Sam x marbles

32 - x : 48 - x = 13 : 21

21(32 - x) = 13(48 - x)

48 = 8x

x = 6

Sarah give Sam 6 marbles

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