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When adding fractions, they should have the same denominator.
When adding fractions, they should have the same denominator.
List the multiples of each number.
Use the least common multiple.
5/8
11/15
8 and 15
See solution.
denominator. In this exercise, we have two fractions with different denominators. Since 8 is a multiple of 4, we can multiply both the numerator and denominator of 14 by 2 to create a common denominator.
<deduct> \dfrac{3}{8}+\dfrac{1}{4} a/b=a * 2/b * 2 \dfrac{3}{8}+\dfrac{1 \cdot {\color{#FF0000}{2}}}{4 \cdot {\color{#FF0000}{2}}} Multiply \dfrac{3}{8}+\dfrac{2}{8}
a/b=a * 3/b * 3
a/b=a * 5/b * 5
Multiply
We want to find the least common multiple of 8 and 4. To do so, we will start by listing the multiples of 8 and 4. Multiples of8=& 8, 16, 24, 32, 40, 48, 56, Multiples of4=& 4, 8, 12, 16, 20, 24, 28, 32 Note that the least common multiple is 8. Now, let's find the LCM of 5 and 3 by listing the multiples of both numbers. Multiples of5=& 5, 10, 15 , 20, 25, , 35, 40, Multiples of3=& 3, 6, 9, 12, 15, 18, 21, 24 The least common multiple of 5 and 3 is 15.
To add or subtract fractions, they should have the same denominator. When we have two fractions with different denominator, we need to find a common denominator. For example, let's recall the sum of Part A. 3/8+1/4=3/8+2/8 Here, we multiplied both numerator and denominator of 14 by 2 because 8 is a multiple of 4 and 8. Sometimes, it will not be as simple as this example. Let's recall the sum of Part B. 2/5+1/3=6/15+5/15 In this case, we used the least common multiple of the denominators. The LCM is the smallest multiple between two numbers, so we can use this number as common denominator. Once we know the common denominator we also know how to rewrite the fractions so that they can be added.
