AMC 8 1989 Problem 7
AMC8 1989 年第 7 题
方程与不等式★★☆☆☆
If the value of 20 quarters and 10 dimes equals the value of 10 quarters and dimes, then n=
如果 20 个 25 分硬币和 10 个 10 分硬币的总价值等于 10 个 25 分硬币和 个 10 分硬币的总价值，则 n=
- A.10
- B.20
- C.30
- D.35
- E.45
正确答案 · Correct Answer
D
解析 · Solution
Solution 1
The total value of 20 quarters and 10 dimes is .
The value of 10 quarters is .
Therefore, the value of dimes is $6.00 - $2.50 = $3.50, so
$$$$$$$$
The dimes' values need to sum to 10 quarters and 10 dimes. we can divide both sides by 10. n=25+10=35 So, our answer is --
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