Solve the following exercise:
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Solve the following exercise:
Let's try to find the lowest common denominator between 2 and 9
To find the lowest common denominator, we need to find a number that is divisible by both 2 and 9
In this case, the common denominator is 18
Now we'll multiply each fraction by the appropriate number to reach the denominator 18
We'll multiply the first fraction by 9
We'll multiply the second fraction by 2
Now we'll combine and get:
\( \frac{2}{4}+\frac{1}{4}= \)\( \)
Since 2 and 9 share no common factors (2 is even, 9 is odd), their LCD is simply their product: . This works for any two numbers that are relatively prime.
Fractions represent parts of a whole. means 1 out of 2 equal parts, while means 2 out of 9 equal parts. You can't combine different-sized pieces without making them the same size first!
Not always! Only when the denominators share no common factors. For example, LCD of 4 and 6 is 12 (not 24), because both are divisible by 2.
Divide the LCD by each denominator: and . These are your multipliers for the numerator and denominator of each fraction.
Always try! Check if the numerator and denominator have common factors. For , since 13 is prime and doesn't divide 18, this fraction is already in simplest form.
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