Solve the following exercise:
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Solve the following exercise:
Let's try to find the lowest common denominator between 7 and 3
To find the lowest common denominator, we need to find a number that is divisible by both 7 and 3
In this case, the common denominator is 21
Now we'll multiply each fraction by the appropriate number to reach the denominator 21
We'll multiply the first fraction by 3
We'll multiply the second fraction by 7
Now we'll combine and get:
Without calculating, determine whether the quotient in the division exercise is less than 1 or not:
\( 5:6= \)
Because fractions represent parts of different wholes! You can't combine (one-seventh) and (one-third) without making the denominators the same first.
Since 7 and 3 are both prime numbers, their LCD is simply 7 × 3 = 21. For prime numbers, you always multiply them together to get the LCD.
Always check! Since 10 and 21 share no common factors (10 = 2×5, 21 = 3×7), the fraction is already in its simplest form.
The process stays the same! Find the LCD, convert both fractions to equivalent fractions with that denominator, then add the numerators. Just take your time with the multiplication.
You could use any common multiple like 42 or 63, but using the least common denominator (21) keeps the numbers smaller and easier to work with.
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