What is 1/9 of 80?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 1/9 of 80? We'll show you a straightforward method to achieve that.
How to calculate 1/9 of 80?
- Multiply the whole number by the numerator of the fraction: 80 × 1 = 80
- Divide this result by denominator of the fraction: 80/9 = 8.8888888888889
Since 80/9 is an improper fraction, the result could also be expressed as a mixed number: 8 8/9
How does it work?
The principle behind finding a fraction of a number, such as 1/9 of 80, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 1/9 of 80)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 9 to isolate x:
- Which gives the result:
Thus, 1/9 of 80 is equal to 80/9 (or 8.8888888888889 in its decimal form).