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  • 表示不同情况的整数


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    Aidin’s homework is to write about the world's highest geological feature. He discovered that Mount Everest reached 29,035 ft above sea level. Mauna Kea, only 13,796 ft above sea level. But since it started beneath the water, its total length from base to height was 33,476 ft. And the Mariana Trench is the deepest trench in the world at 36,070 ft! Which feature should Aidin write about?
    ::艾登的功课是写下世界最高地质特征。 他发现珠穆朗玛峰的海拔达到29,035英尺。 Mauna Kea仅高于海平面13,796英尺。 但自从它从水下开始,其从基底到高度的总长度为33,476英尺。 马里亚纳海沟是世界上最深的海沟,海拔为36,070英尺。 Aidin应该写什么特征?

    In this concept, you will learn how to use integers to represent different situations in the real world.
    ::在这个概念中,你将学会如何使用整数来代表现实世界中的不同情况。

    Integers to Represent Different Situations
    ::代表不同情况的综合体

    There are many different kinds of numbers. 
    ::数字有多种不同的种类。

    A  whole number  is any counting number. Numbers, like 1/2 or .75, that you use to describe a part of something are not  whole numbers .
    ::一个整数是任意数。您用来描述某事物一部分的数字,如 1/2 或 .75,不是整数。

    A  positive  number  is a number greater than  zero . It can be written with or without a + symbol in front of it. A gain in something is written with a positive number. Profit, increase, and income are all examples of words that mean positive.
    ::正数是大于零的数。 它可以在前面用或不用+符号书写。 某事物的增益是用正数书写。 利润、 增长和收入都是表示正数的字词例子。

    A  negative number  is a number that is less than zero. It is always written with a - symbol in front of it. A loss is written with a negative number. Decrease, spend, and decline are examples of words that mean negative.
    ::负数是一个小于零的数字。 它总是在前面写上一个符号。 损失则用负数写上。 减少、 花费和下降是表示负数的字数的例子。

    An  integer  is any positive whole number or its negative. Zero is also considered an integer.
    ::整数为正整数或负整数。零也被视为整数。

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

    .

    On this thermometer the temperature reads 100º. The temperature is above zero. That means that it is positive. Therefore, we can write it either as +100 or just as 100. A temperature that is below zero is negative. A temperature that is 5 degrees below zero, therefore, is written -5.
    ::在此温度计上温度为100o。 温度高于零。 这意味着温度为正数。 因此, 我们可以将其写为+100或100。 低于零的温度为负数。 因此, 温度为零下5°, 等于零下5° 。

    Here is another example.
    ::下面是另一个例子。

    Determine whether the integer given is positive or negative and write it out:
    ::确定给定的整数是正的还是负的, 并写入 :

    Sasha goes to the mall and spends $45.00 from her bank account at the clothing store.
    ::Sasha去商场 花45美元 她的银行帐户 在服装店。

    First, determine whether Sasha gains or loses money.
    ::首先,确定萨沙是赢还是输

    Sasha "spends" this money, so she no longer has it. This makes it a loss.
    ::Sasha"存"了这笔钱,所以她不再有了,这就损失了

    Then, write it as a negative integer.
    ::然后写成负整数

    The answer is -45.
    ::答案是 -45

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Aidin and his science report.
    ::早些时候,你被问及 艾登和他的科学报告的问题。

    He has to choose between Mount Everest, at 29,035 ft above sea level, Mauna Kea which is 33,476 ft from its base to peak, but only 13,796 ft above sea level, and the Mariana Trench, which is actually the deepest point in the world, starting at 36,070 ft below sea level. His report is on the "highest" geological feature - which one does he write about?
    ::在珠穆朗玛峰,海拔29,035英尺,摩纳基亚(Mauna Kea)从基点到峰点为33,476英尺,但海拔仅13,796英尺,和马里亚纳海沟(Mariana Trench)之间,他必须作出选择,后者实际上是世界最深点,从海平面下36,070英尺开始。他的报告是关于“最高”地质特征的,他写了什么?

    The "highest" geological feature is the one that stretches the farthest above sea level. In other words, the biggest integer.
    ::“ 最高” 地质特征是 最远的海平面。 换句话说, 最大的整数 。

    First, he writes them each as an integer.
    ::首先,他把每一个写成一个整数。

    Mount Everest is 29,035 ft above sea level.
    ::珠穆朗玛峰海拔29 035英尺

    "Above sea level" means it is positive.
    ::"波及海平面"的意思是肯定的

    Then he writes it as a positive integer.
    ::然后写成正整数

    Mount Everest is +29,035
    ::珠穆朗玛峰是+29,035

    Mauna Kea is trickier. It is 33,476 ft tall. But it is only 13,796 ft above sea level. 
    ::Mauna Keea更狡猾,有33,476英尺高,但仅高于海平面13,796英尺。

    That means it is 13,796ft positive. 
    ::这意味着是13,796ft正数。

    The rest of its length is beneath the water, below sea level, so it doesn't count.
    ::其余的长度在水下,海平面下 所以不算数

    Then, he writes the part that is positive as a positive integer.
    ::然后,他写了正面部分,作为正整数。

    Mauna Kea is +13,796
    ::Mauna Keea是+13,796

    The Mariana Trench is 36,070 ft below sea level.
    ::马里亚纳海沟在海平面以下36 070英尺。

    "Below sea level" means that it is negative.
    ::"海平面以下"意味着它是负的。

    Then, he writes it as a negative integer.
    ::然后,他把它写成负整数

    The Mariana Trench is -36,070.
    ::马里亚纳海沟是36 070

    Next, he writes them in a list to compare them.
    ::接下来,他把它们写成一个清单 来比较它们。

    Mount Everest: +29,035
    ::山珠峰:+29,035

    Mauna Kea: +13,796
    ::Mauna Keea:+13,796

    The Mariana Trench: -36,070
    ::马里亚纳海沟: - 36 070

    Finally, he picks the one that is the biggest positive integer.
    ::最后,他选择了最大正整数的正整数。

    That is Mount Everest.
    ::那是珠穆朗玛峰

    The answer is Mount Everest is the highest geological feature in the world.
    ::答案是珠穆朗玛峰是世界上最高的地质特征。

    Example 2
    ::例2

    People invest money in the stock market all the time. Sometimes the overall market increases and their money grows. Sometimes it decreases and they lose money. The  amount  of increase or decrease is characterized by positive or negative "points." Which of the following situations is expressed by a negative integer?
    ::人们总是在股市上投资,有时整个市场增长和货币增长,有时市场下降和货币损失。 增减的特点是正或负“点 ” 。 以下哪一种情况以负整数表示?

    1. No gain or loss in the stock market
      ::股票市场无损益

     There is no loss or gain. Therefore, the integer used to describe it is zero, which is  neither negative nor is it positive.
    ::没有损益。 因此,用于描述它的整数为零,既不是负数,也不是正数。

    1. The average plummeted 15 points
      ::平均跌跌15点

     The word "plummeted" indicates an extreme loss. Therefore, it would be written as  -15. This is a negative integer, so it is the answer.
    ::“ 排除” 一词表示一种极端的损失。 因此, 它会以 - 15 来写 。 这是一个负整数, 所以它就是答案 。

    1. The overall rise was 30%
      ::总体增长率为30%

     The market is characterized as rising, which is positive. However, a  percentage  is  not a whole number, so it is not an integer.
    ::市场的特点是上升,这是正数,但百分比不是整数,因此不是整数。

    Write out each of the following situations as an integer.
    ::将下列各情况以整数形式列出。

    Example 3
    ::例3

    The head of the volcano is located 50 feet below sea level.
    ::火山头部位于海平面下50英尺处。

    First, determine whether the location is positive or negative.
    ::首先,确定位置是正的还是负的。

    Sea level is zero in this example. That means that "below sea level" is negative.
    ::在这个例子中,海平面为零。 这意味着“海平面以下”是负的。

    Then, write it as a negative integer.
    ::然后写成负整数

    The answer is   − 50 .
    ::答案是 - 50

    Example 4
    ::例4

    Rahul spent $100.00 on baseball cards.
    ::Rahul在棒球卡上花费了100美元。

    First, determine whether Rahul gained or lost money.
    ::首先,确定Rahul是获得还是损失了钱财。

    He "spent" it. That means he no longer has it. So it is a loss.
    ::"他"的意思就是他不再拥有它 所以是个损失

    Then, write it as a negative integer.
    ::然后写成负整数

    The answer is  − 100 .
    ::答案是 -100

    Example 5
    ::例5

    Alaska experienced a heat wave of  98 ∘  on July 4th.
    ::阿拉斯加在7月4日经历了98度的热浪。

    First, determine whether the temperature is above or below zero.
    ::首先,确定温度是高于零还是低于零。

    A "heat wave" means it's very hot. If it were below zero, it would be very cold. That means it is positive.
    ::"热浪"表示它非常热,如果它低于零,它会非常寒冷。这意味着它呈阳性。

    Then, write it as a positive integer.
    ::然后写成正整数

    The answer is  + 98 .

    ::答案是+98。

    Review
    ::回顾

    Write an integer to represent each situation.
    ::写一个整数来代表每个情况 。

    1. A loss of 20 points
      ::损失20点
    2. A gain of 14 points
      ::增加14点
    3. A profit of $20.00
      ::利润$20.00
    4. A loss of $18.00
      ::损失18.00美元
    5. An elevation of 500 ft.
      ::高500英尺高
    6. 200 feet below sea level
      ::低于海平面200英尺以下
    7. 8 degrees below zero
      ::零下8度以下零下8度
    8. 78 degrees
      ::78度 78度
    9. A decrease of $68.00
      ::减少68.00美元
    10. An increase of $55.00
      ::增加55.00美元
    11. The price of a stock did not rise nor fall today but remained the same.
      ::股票的价格今天没有上涨,也没有下降,但保持不变。
    12. The plane descended at a rate of 15%.
      ::飞机以15%的速度下降
    13. A submarine floating on the ocean surface.
      ::一艘潜水艇漂浮在海面上
    14. The cost and the earnings evened out.
      ::成本和收入均匀。
    15. The stock market had an overall rate of 18% above.
      ::股票市场的总利率高于18%。