What is 3/9 of 25?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 3/9 of 25? We'll show you a straightforward method to achieve that.
How to calculate 3/9 of 25?
- Multiply the whole number by the numerator of the fraction: 25 × 3 = 75
- Divide this result by denominator of the fraction: 75/9 = 8.3333333333333
- Simplify by dividing both the numerator and denominator by their GCD (3):
- 75/3 = 25
- 9/3 = 3
- Which gives: 25/3
Since 25/3 is an improper fraction, the result could also be expressed as a mixed number: 8 1/3
How does it work?
The principle behind finding a fraction of a number, such as 3/9 of 25, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 3/9 of 25)
- 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, 3/9 of 25 is equal to 25/3 (or 8.3333333333333 in its decimal form).