PP-T2-DS51

[Huang Hsin-Yi]

51. 4198-!-item-!-187;#058&003817
Whenever Martin has a restaurant bill with an amount between $10 and $99, he calculates the dollar amount of the tip as 2 times the tens digit of the amount of his bill. If the amount of Martin's most recent restaurant bill was between $10 and $99, was the tip calculated by Martin on this bill greater than 15 percent of the amount of the bill?

(1) The amount of the bill was between $15 and $50.

(2) The tip calculated by Martin was $8.

Ans:B

(1)找不到任何數字可低於15%
如50-tip=10----20%
21-tip=6-----28%
41-tip=10----24%

因此A為何不行?

[amazingslim]

我看不懂你的解法
以下是我的解法
(1) The amount of the bill was between $15 and $50.
$15 , tip=2, tip百分比=2/15=13.33%
$50 , tip=10, tip百分比=10/50=20%

[Huang Hsin-Yi]

he calculates the dollar amount of the tip as 2 times the tens digit of the amount of his bill
原來我看錯了,這句話的翻譯了

[chiungfen]

he calculates the dollar amount of the tip as 2 times the tens digit of the amount of his bill


請問這句話是什麼意思呢?

是指 tip 是bill 的多少倍?

不太了解