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  • 包含折扣的价格

    lesson content

    Penny wants a new television. She sees that the one she wants is on sale at two different stores. The original price is $399. First, Pick is having a 25% off sale on all TVs. Halmarket is selling the same TV for $299. Which store has the better deal?
    ::Penny想要一台新的电视。她看到她想要的电视在两家不同的商店销售。最初的价格是399美元。首先,Pick在所有电视上都售出25%。Halmarket出售同一台电视299美元。哪家店有更好的交易?

    In this concept, you will learn how to find prices involving discounts.
    ::在此概念中,您将学会如何找到涉及折扣的价格。

    Finding Prices Involving Discounts
    ::涉及贴现的物价调查

    A  discount  is the  difference  between the original price and the reduced price. It is described as a number of dollars or as a percent.
    ::折扣是原价和减价之间的差额,称为美元数或百分比。

    Find the reduced price in two steps:
    ::将降价分为两步:

    First, find the dollar  amount  of the discount. Multiply the original price by the discount.
    ::首先,找到折价的美元数额。乘以原价乘以折价。

    Next, subtract the dollar value of the discount from the original price. The total is the reduced price of the item.
    ::接下来,从原价中减去折价的美元价值。总计是物品的降价。

    Let’s look at an example.
    ::让我们举个例子。

    Tracy went shopping for a new pair of sneakers. She found a blue pair that was $58. The sign said that they were 15% off the original price. How much is the discount? How much did Tracy end up paying for the sneakers?
    ::Tracy去买一双新的运动鞋。 她发现一对蓝色的,是58美元。 牌子上写着它们比原价低15 % 。 折扣是多少? Tracy最后为运动鞋付了多少钱?

    First, find the discount amount. Find 15% of $58. 15% is also 0.15. Multiply the original price by the discount.
    ::首先,找到贴现金额。 找到58美元的15%。 15%也是0. 15。 乘以折价的原价 。

    58 × 0.15 = 8.70

    Next, subtract the discount from the original price.
    ::接下来,从原价中减去折扣。

    58 − 8.70 = 49.30

    The discount was $8.70. Tracy paid $49.30 for the sneakers.
    ::Tracy为运动鞋支付了49.30美元。

    You can also find the reduced price by multiplying the original price by the percent of the price you will pay. The percent you are paying is 100% minus the discount %.
    ::您也可以通过将原价乘以您将支付的价格的百分率来找到降价。您要支付的百分比是100%减去折价的百分率。

    Let’s look at Tracy’s sneakers again.
    ::让我们再看看Tracy的运动鞋。

    The sneakers are 15% off. Use mental math to calculate the percent Tracy will be paying. Think, “100 minus 15 is 85.”
    ::运动鞋是15 % 的关卡。 使用心理数学计算 Tracy 将支付的百分比。 想想 , “ 100 减去 15 等于 85 ” 。

    Next, multiply the original price by the percent she will be paying. 85% is also 0.85.
    ::接下来,将原价乘以她将支付的百分比。 85%也是0.85。

    58 × 0.85 = 49.30

    This also gives the reduced price of the sneakers, $49.30.
    ::这也降低了运动鞋的价格49.30美元。

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Penny and the TVs.
    ::早些时候,你被问及Penny和电视机的问题

    Pick has it on sale for 25% off and Halmarket has it on sale for $299. Originally the price was $399. To compare the prices, Penny needs to find the sale price of the TV at First Pick.
    ::为了比较价格,Penny需要在《第一选牌》上找到电视的销售价格。

    First, find the discount amount. Find 25% of $399. 25% is also 0.25. Multiply the original price by the discount.
    ::首先,找到贴现金额。找到25%的399美元,25%的25%也是0.25美元。乘以原来的折扣价格。

    399 × 0.25 = 99.75

    Next, subtract the discount from the original price.
    ::接下来,从原价中减去折扣。

    399 − 99.75 = 299.25

    The TV at First Pick is on sale for $299.25. Compare $299.25 to the price of the TV at Hal market, $299.
    ::第一选局电视台售价为299.25美元,与哈尔市场电视价格299美元相比,售价为299.25美元。

    The TV is cheaper at Hal market, but only by $0.25.
    ::在哈尔市场,电视更便宜,但只有0.25美元。

    Example 2
    ::例2

    Find the discount and the reduced price.
    ::寻找折扣和减价。

    Kara bought a new dress. The original price of the dress was $65.50. There was a 15% discount on the dress.
    ::Kara买了件新衣服,原来的价格是65.50美元,服装上有15%的折扣。

    What was the amount of the discount? How much did Kara pay for the dress?
    ::折扣的金额是多少?

    First, find the discount amount. Find 15% of $65.50. 15% is also 0.15. Multiply the original price by the discount.
    ::首先,找到贴现金额。 找到65. 50的15%。 15%也是0. 15。 乘以原来的折扣价格 。

    65.50 × 0.15 = 9.83

    (Note: Dollars are only measured to the second decimal digit.  Round  9.825 to the nearest hundredths place.)
    :伤心注:美元仅测量到小数点后两位数。 第9.825回合至最近的第一百位。 )

    Next, subtract the discount from the original price.
    ::接下来,从原价中减去折扣。

    65.50 − 9.83 = 55.67

    The discount was $9.83. Kara spent $55.67 on the dress.
    ::卡拉在裙子上花了55.67美元

    Example 3
    ::例3

    If a $50.00 shirt is 25% off, how much would you pay for the shirt?
    ::如果一件50块的衬衫脱了25% 你会付多少钱买这件衬衫?

    First, find the discount amount. Find 25% of $50. 25% is also 0.25. Multiply the original price by the discount.
    ::首先,找到贴现金额。找到50美元的25%。25%也是0.25。乘以原来的折扣价格。

    50 × 0.25 = 12.50

    Next, subtract the discount from the original price.
    ::接下来,从原价中减去折扣。

    50 − 12.50 = 37.50

    You would pay $37.50.
    ::你会付37.50美元

    Example 4
    ::例4

    If a video game that usually costs $45.50 is 30% off, how much would you pay for the game?
    ::如果一个通常花费45.50美元的视频游戏是30%的关闭, 你会为游戏付出多少钱?

    First, use mental math to find the  percentage  you would end up paying for the video game. Think, “If the discount is 30%, I would pay 70% of the price.” 70% is also 0.7.
    ::首先,使用心理数学来寻找最终你为游戏付费的百分比。 想想 , “ 如果折扣是30%,我会支付70%的价格 ” 。 70 % 也是0.7%。

    Then, multiply the original price by percent you would pay.
    ::然后,将原价乘以您将支付的百分率。

    45.50 × 0.7 = 31.85

    You would pay $31.85.
    ::你会付31.85美元

    Example 5
    ::例5

    If a backpack was reduced to $30 and the original price was $40, what percent was the discount?
    ::如果背包减为30美元,而原来的价格是40美元,那么折扣的百分率是多少?

    First, use the given information to find the reduced amount. The reduced amount is the difference between the original price and the sale price.
    ::首先,使用给定的信息查找减少的金额。减少的金额是原价与销售价之间的差额。

    40 − 30 = 10

    Next, write an equation to find the discount percent. Remember, the original price multiplied by the discount percent is the reduced amount. Use  x  to represent the unknown discount percent.
    ::下一步, 写一个方程式以找到折价百分比。 记住, 原价乘折价百分比乘以折价百分比就是减价数额。 使用 x 表示未知的折价百分比 。

    40 x = 10

    Then, solve for  x  to find the discount percent.
    ::然后解决x找到折扣率的问题

    40 x 40 = 10 40 x = 0.25

    Finally, convert the decimal to a percent.
    ::最后,将小数点转换为百分之一。

    0.25 = 25 %

    The backpack was discounted 25%.

    ::背包被折扣25%。

    Review
    ::回顾

    Find the reduced price. Round your answer to the nearest whole cent.
    ::找到减价的价钱 把你的答案转回最近的整分数

    1. Original price: $19.95, discount 15%
      ::原价:19.95美元,折价15%
    2. Original price: $20.00, discount 50%
      ::原价: 20美元,折价50%
    3. Original price: $35.50, discount 10%
      ::原价:35.50美元,折价10%
    4. Original price: $50.00, discount 30%
      ::原价: 50.00美元,折价30%
    5. Original price: $100.00, discount 20%
      ::原价:100美元,折价20%
    6. Original price: $75.00, discount 30%
      ::原价:75.00美元,折价30%
    7. Original price: $29.95, discount 20%
      ::原价:29.95美元,折价20%
    8. Original price: $18.00, discount 10%
      ::原价:18美元,折价10%
    9. Original price: $47.50, discount 10%
      ::原价:47.50美元,折价10%
    10. Original price: $75.00, discount 30%
      ::原价:75.00美元,折价30%
    11. Original price: $125.00, discount 20%
      ::原价: 125.0美元,折价20%
    12. Original price: $225.50, discount 10%
      ::原价:225.50美元,折价10%
    13. Original price: $456.00, discount 25%
      ::原价:456.00美元,折价25%
    14. Original price: $530.00, discount 30%
      ::原价: 530.00美元,折价30%
    15. Original price: $750.00, discount 12%
      ::原价:750.00美元,贴现12%

    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