Solve the following exercise:
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Solve the following exercise:
Let's try to find the lowest common denominator between 5 and 4
To find the lowest common denominator, we need to find a number that is divisible by both 5 and 4
In this case, the common denominator is 20
Now we'll multiply each fraction by the appropriate number to reach the denominator 20
We'll multiply the first fraction by 4
We'll multiply the second fraction by 5
Now we'll combine and get:
\( \frac{2}{4}+\frac{1}{4}= \)\( \)
List the multiples of each number: 5 (5, 10, 15, 20, 25...) and 4 (4, 8, 12, 16, 20, 24...). The smallest number that appears in both lists is your LCD - in this case, 20!
Because fractions represent parts of different-sized wholes! means 2 pieces out of 5, while means 1 piece out of 4. You need to make the pieces the same size first.
Not necessarily! Sometimes the LCD is large, especially when the denominators don't share common factors. Double-check by ensuring your LCD is divisible by both original denominators.
Yes, when possible! Check if the numerator and denominator share any common factors. In this problem, is already in simplest form since 13 and 20 share no common factors.
You can use any common denominator, but using the LCD makes the math easier with smaller numbers. Using 40 instead of 20 would work but create unnecessarily large fractions!
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