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  • 估算技巧

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    Shen and his family went to a restaurant to celebrate his last day of school. When the bill arrived the total came to $45.20. Shen knows they are supposed to leave a  tip  on the total  amount . How much of a tip should they leave and what is the total amount of the bill including the tip?
    ::Shen和他的家人去一家餐馆庆祝他最后一天的学校。当法案到达时,总金额达到45.20美元。 Shen知道他们应该给总额留一个小费。他们应该离开多少小费以及包括小费在内的总金额是多少?

    In this concept, you will learn to estimate appropriate tips.
    ::在这一概念中,你会学会估计适当的小费。

    Estimating Tips
    ::估算提示

    A  tip  is an amount of money that is given to a worker, such as a waiter or luggage handler, who performs a service for you. A common tip amount is 15% of the cost of the meal or other service. Since you don’t usually calculate a tip exactly, you can estimate the amount of a tip.
    ::提示是给一个为您提供服务的工人(如服务员或行李处理员)的一笔金额。 通常的提示金额是餐费或其他服务费的15%。 由于您通常不精确计算提示,您可以估算提示金额。

    Follow these steps to estimate a 15% tip:
    ::遵循这些步骤来估计15%的提示 :

    First,  round  the total bill to the nearest whole dollar amount.
    ::首先,将总帐单转至最近的整美元数额。

    Next, find 10% of this amount by moving the  decimal point  one place to the left.
    ::下一步,通过将小数点一移到左边,找到这个数额的10%。

    Now, find half of the amount you found in Step 2. This will give you 5% of the total cost.
    ::现在,找到你在第二步中发现的一半金额, 相当于总成本的5%。

    Then, add the 10% amount and the 5% amount together. This will give you your total tip.
    ::然后加上10%的金额和5%的金额。这会给你总的小费。

    Let’s apply these steps by taking a look at an example.
    ::让我们以身作则来运用这些步骤。

    Estimate a 15% tip on a meal that costs $29.75.
    ::估计一顿饭要花15%的小费 需要29.75美元

    First, round $29.75 to $30.
    ::第一轮,29.75美元到30美元

    Next, find 10% of  $ 30 = $ 3.00
    ::下一个,发现 30美元的10% = 3.00美元

    Now, find half of 10%: Half of  $ 3.00 = $ 1.50
    ::现在,找到10%的一半:3.00美元=1.50美元的一半。

    Then, add 10% and 5%:  $ 3.00 + $ 1.50 = $ 4.50

    ::然后,加上10%和5%:3.00美元+1.50美元=4.50美元

    A 15% tip on a meal that costs $29.75 is about $4.50.
    ::15美分的一顿饭 花费29.75美元 大约是4.50美元

    Let’s take a look at another example.
    ::让我们看看另一个例子。

    A tip doesn’t always have to be 15%. It can be more or less depending on the level of service you received. If your waitress was especially good you may decide to give her a bigger tip. Estimate a 20% tip on a restaurant bill of $38.95.
    ::提示并不一定总是15 % 。 它可能或多或少取决于您得到的服务水平。 如果服务员表现特别好,您可以决定给她一个更大的提示。 一份38.95美元的餐厅账单上大约20%的提示。

    You can start by thinking about 10% of this bill. Since that involves simply moving the decimal point, you can say that the estimate of 10% is $3.90.
    ::你可以首先考虑10%的帐单。因为这意味着只需移动小数点,你可以说10%的估计数是3.90美元。

    Now 20% is double that to $7.80.
    ::现在20%是两倍到7.80美元

    You can say that an estimate of a 20% tip is in a range from  $ 7.50 − $ 8.00 .
    ::你可以说,20%的小费的估计数在7.50美元到8.00美元之间。

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Shen’s end-of-school celebration meal.
    ::更早之前,

    The total of the family’s bill came to $45.20. How much of a tip should they leave and what is the total amount of the bill including the tip?
    ::家庭法案总额达到45.20美元。 他们应该离开多少小费以及包括小费在内的法案总额是多少?

    Recall that the tip should be based on the level of service received. For good service you should leave 15%. For exceptional service, you might want to leave 20%.
    ::请注意,提示应该基于所接受的服务水平。如果服务良好,您应该离开15%。对于特殊服务,您应该离开20%。

    First, round $45.20 to $45.00.
    ::第一轮45.20到45.00

    Next, find 10% of  $ 45 = $ 4.50
    ::接下来,发现45美元=4.50美元的10%

    Now, find half of  $ 4.50 = $ 2.25
    ::现在,找到一半的4.50美元=2.25美元。

    Then, for a 15% tip add  10 % + 5 % : $ 4.50 + $ 2.25 = $ 6.75
    ::然后,对于15%的小费,加上10%+5%:4.50美元+2.25美元=6.75美元

    Finally, for 20% double 10%:  2 ( 4.50 ) = $ 9.00
    ::最后,20%翻一番,10%:2(4.50)=9.00美元

    The answer is Shen's family should leave a tip between $6.75 and $9.00, so the total amount of their bill, including tip, is between  $ 51.95 ( $ 45.20 + $ 6.75 )  and  $ 54.20 ( $ 45.20 + $ 9.00 ) .
    ::答案是沈家家应该留下6.75美元到9.00美元之间的小费,因此他们的账单总额,包括小费在内,在51.95美元(45.20美元+6.75美元)和54.20美元(45.20美元+9.00美元)之间。

    Example 2
    ::例2

    Estimate a 20% tip on a meal that costs $54.15.
    ::估计一顿需要54.15美元的饭 需要20%的小费

    Since the tip is about 20%, you can find 10% and then double it.
    ::因为小费大约是20%, 你可以找到10%,然后翻倍。

    First, round $54.15 to $54.
    ::第一,54.15美元到54美元

    Next, find 10% of  $ 54 = $ 5.40
    ::接下来,发现54美元=5.40美元的10%

    Then, find 20% of  $ 54 = 2 × $ 5.40 = $ 10.80
    ::然后,发现54美元=2x5.40美元=10.80美元的20%

    A 20% tip on a meal that costs $54.15 is about $10.80.
    ::20%的餐费54.15美元 大约是10.80美元

    Example 3
    ::例3

    Estimate a 15% tip for a $29.00 bill. Provide a range in your answer.
    ::估计一张29.00美元的帐单有15%的提示。在您的答复中提供一个范围 。

    First, $29.00 is already rounded.
    ::首先,29.00美元已经四舍五入了

    Next, find 10% of  $ 29 = $ 2.90
    ::接下来,发现29美元=2.90美元的10%

    Now, find half of  $ 2.90 = $ 1.45  
    ::现在,找到290美元=1.45美元的一半

    Then, add 10% and 5%:  $ 2.90 + $ 1.45 = $ 4.35
    ::然后,加上10%和5%:2.90美元+1.45美元=4.35美元

    A 15% tip on a meal whose cost is $29.00 is between $4.00 and $4.50.
    ::15美分的餐费为29.00美元,在4.00至4.50美元之间。

    Example 4
    ::例4

    Estimate a 15% tip for a $16.00 bill. Provide a range in your answer.
    ::$16. 00 帐单的15%的提示。 在您的答复中提供一个范围 。

    First, $16.00 is already rounded.
    ::首先,$16.00已经四舍五入。

    Next, find 10% of  $ 16 = $ 1.60  
    ::下一步,发现16美元=1.60美元的10%

    Now, find half of  $ 1.60 = $ 0.80  
    ::现在,找出1.60美元=0.80美元的一半

    Then, add 10% and 5%:  $ 1.60 + $ 0.80 = $ 2.40
    ::然后,加上10%和5%:1.60美元+0.80美元=2.40美元

    A 15% tip on a meal that costs $16.00 is between $2.00 and $2.50.
    ::15美分的一顿饭 价钱16.00美元 介于2美元到2.50美元之间

    Example 5
    ::例5

    Estimate a 15% tip for a $55.00 bill. Provide a range in your answer.
    ::估计55.00美元的帐单有15%的提示。在您的答复中提供一个范围 。

    First, $55.00 is already rounded.
    ::首先,55.00美元已经四舍五入。

    Next, find 10% of  $ 55 = $ 5.50
    ::接下来,发现55美元=5.50美元的10%

    Now, find half of  $ 5.50 = $ 2.75  
    ::现在,找到5.50美元=2.75美元的一半

    Then, add 10% and 5%:  $ 5.50 + $ 2.75 = $ 8.25
    ::然后,加上10%和5%:5.50美元+2.75美元=8.25美元

    A 15% tip on a meal that costs $55.00 is between $8.00 and $8.50.
    ::15美分的一顿饭费55.00美元 在8.00美元到8.50美元之间

    Review
    ::回顾

    Estimate a tip of 20% for each amount.
    ::估计每笔金额的点数为20%。

    1. A tip on $15.00
      ::$15.00的小费
    2. A tip on $28.00
      ::28.00美元一小费
    3. A tip on $25.00
      ::25.00美元的小费
    4. A tip on $35.00
      ::关于35.00美元的小费
    5. A tip on $45.00
      ::45.00美元的小费
    6. A tip on $50.00
      ::50.00美元的小费
    7. A tip on $90.00
      ::$90.00的小费$90.00
    8. A tip on $120.00
      ::$120美元上一个小费$120.00
    9. A tip on $125.00
      ::$125.00的小费$125.00$
    10. A tip on $110.50
      ::110.50美元的小费
    11. A tip on $130.75
      ::130.75美元的小费
    12. A tip on $135.50
      ::关于135.50美元的小费
    13. A tip on $98.78
      ::关于9878美元的情报
    14. A tip on $89.67
      ::89.67美元的小费
    15. A tip on $100.20
      ::有关100元的线报 20

    Review (Answers)
    ::回顾(答复)

    Click   to see the answer key or go to the Table of Contents and click on the Answer Key under the 'Other Versions' option.
    ::单击可查看答题键, 或转到目录中, 单击“ 其他版本” 选项下的答题键 。

    Resources
    ::资源