如何添加带负数的分数?
分数是定义为整体的一部分的数值。它来源于“fractio”这个词,意思是打破。它用于解决日常生活中的问题,如食物、物资、货币等的划分。a/b形式的数字可以称为分数。其中 a、b 是任意数字。例如 2/3、12/4 等。形式为 a/b 的有理数、无理数可以视为分数。
分数的一部分
分数由两部分组成:
- 分母:分数的最低部分称为分母。它表示给定的整数将被分成多少部分。例如,2/3,这里 3 被称为分母。
- 分子:分数的上半部分称为分子。它表示分数在哪几个部分。例如 2/3,这里 3 被称为分子
分数类型
以下是分数的类型:
- 真分数:真分数是分子总是小于分母的分数。例如,5/16、1/4 等。
- 不适当的分数:不适当的分数是分子总是大于或等于其分母的那些分数。例如,5/2、11/4 等。
- 单位分数:单位分数是分子只有 1 的分数。例如,1/2、1/14 等。
- 混合分数:混合分数是包含全分数和适当分数的混合物的分数。例如, , 等等。
- 等效分数:等效分数是包含相同值的分数。例如,2/9 x 2/2 = 4/18。
- 相似分数:相似分数是包含相同分母的分数。例如,2/8、4/8 等。
- 与分数不同:与分数不同的是那些包含不同分母的分数。例如,2/9、8/13 等。
添加带负数的分数
众所周知,加法是数学的基本运算。它用于求两个正数或负数之和。我们还可以添加具有相同或不同分母的分数。我们也可以添加带负数的分数。当我们在任何正数或负数之间执行加法或减法时,我们需要记住一些规则。这些在下面提到 -
Rule 1: When two positive numbers are multiplied we get positive result.
(+) x (+) = +
Example: 5×2=10
Rule 2: When two negative numbers/symbols are multiplied we get positive result.
(-) x (-) = +
Example: (-7)×(-2)= 14
Here two negative symbols are cancelled to each other.
Rule 3: When a positive and negative integers are multiplied then resultant number will be negative.
(-) x (+) = –
Example: (-7) x 2 = -14
所以我们需要在执行分数和负数之间的加法时考虑这些规则。
添加负数分数的步骤:
We have a fraction a/b and a negative number -c. Now we add them using the following steps:
Step 1: Convert their symbols according to the above rule. Here, a/b + (-c) = a/b – c
Step 2: a/b – c can also written as a/b -c/1
Step 3: Now take the LCM on b and 1
Step 4: Now the final equation is (a – c)/b and solve this equation to get the final result.
示例问题
问题 1:(1/2) + (-1) = ?
解决方案:
Here we have + operation before a negative number. According to rule-3 when we multiply + with – we get negative symbol.
(1/2) + (-1) will be converted to (1/2) – 1
This (1/2) – 1 can be rewritten into (1/2) – (1/1)
LCM of 2 denominators 2,1 is 2.
(1/2) – (1/1) = (1 – 2)/2
= -1/2
= -0.5
问题 2:-(1/2) + (-1) = ?
解决方案:
Here we have + operation before a negative number. According to rule-3 when we multiply + with – we get negative symbol.
-(1/2) + (-1) will be converted to -(1/2) – 1
This -(1/2) – 1 can be rewritten into (-1/2) – (1/1)
LCM of 2 denominators 2,1 is 2.
(-1/2) – (1/1) = (-1 – 2)/2
= -3/2
= -1.5
问题 3:-(1/3) + (3/6) = ?
解决方案:
LCM of 2 denominators 3, 6 is 6.
(-1/3) + (3/6) = (-2 + 3)/6
= 1/6
问题 4:-(1/3) + (3/8) = ?
解决方案:
LCM of 2 denominators 3,8 is 24.
(-1/3) + (3/8) = ( (-1 x 8) + (3 x 3) )/24
=(-8 + 9) /24
= 1/24
问题 5:-(1/3) + (-2) = ?
解决方案:
Here we have + operation before a negative number. According to rule-3 when we multiply + with – we get negative symbol.
(-1/3) + (-2) will be converted to (-1/3)-(2)
This -(1/3) – 2 can be rewritten into (-1/3) – (2/1)
LCM of 2 denominators 3, 1 is 3.
(-1/3) – (2/1) = (-1 – 2)/3
= -3/3
= -1