What is 1/9 of 78?
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 78? We'll show you a straightforward method to achieve that.
How to calculate 1/9 of 78?
- Multiply the whole number by the numerator of the fraction: 78 × 1 = 78
- Divide this result by denominator of the fraction: 78/9 = 8.6666666666667
- Simplify by dividing both the numerator and denominator by their GCD (3):
- 78/3 = 26
- 9/3 = 3
- Which gives: 26/3
Since 26/3 is an improper fraction, the result could also be expressed as a mixed number: 8 2/3
How does it work?
The principle behind finding a fraction of a number, such as 1/9 of 78, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 1/9 of 78)
- 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: (or )
Thus, 1/9 of 78 is equal to 26/3 (or 8.6666666666667 in its decimal form).