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原文章由 crystalwesley 於 08-3-18 11:44 發表 
There are a total of 30$50-cent coins and $2-coins in a moneybox, and the total value of the coins is $42. How many coins of each denomination are there in the moneybox? (use linear equations ):questi ...
Let X be the quantity of $50cents coins, and Y be the quanity of $2 coins
X + Y = 30
0.5X + 2Y = 42
you need to try to solve the equation by yourself, otherwise you cannot improve your mathematics |
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發表於 08-3-18 11:54