Today we will take a look at how to subtract a mixed number from a whole number. Let’s walk through the examples step by step.
Content:
Before getting into it, remember that a proper fraction is a fraction where the numerator (the top number) is less than the denominator (the bottom number). In addition, a mixed number is the sum of a whole number and a proper fraction. See the example below.
1) Subtract 8 – 52/3:
Since the denominator in the fractional part of the mixed number is 3, we convert the whole number and the mixed number to fractions with a denominator of 3. To convert the whole number 8 to a fraction with a denominator of 3, multiply 8 by 3 and then, divide that product by 3. To convert a mixed number to an improper fraction, multiply the denominator by the whole number, and then, add this result to the numerator.
Next, we subtract the fractions 24/3 and 17/3. It’s a piece of cake given that the have the same denominator.
The resulting fraction 7/3 is an improper fraction, that we need to convert to a mixed number. Don’t forget that an improper fraction is a fraction where the numerator is greater than or equal to the denominator.
The final answer is 21/3.
2) Subtract 9 – 43/5:
Given that the denominator of the fractional part of the mixed number is 5, we rewrite both, the whole number 9 and the mixed number 43/5 as fractions with a denominator of 5.
In the following step, we find the difference between 45/5 and 23/5.
Since we have a mixed number in the initial statement, lastly, we convert the improper fraction 22/5 to a mixed number.
The resulting mixed number is 42/5.
Video
In the following video, we will see more examples.
Reference
If you want to go deeper into this topic, check out this reference:
- Tussy, K., Gustafson, D. y Koenig, D. (2013). Prealgebra (4th ed.; p. 382). Cengage Learning.