What is 9/5 of 18?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 9/5 of 18? We'll show you a straightforward method to achieve that.
How to calculate 9/5 of 18?
- Multiply the whole number by the numerator of the fraction: 18 × 9 = 162
- Divide this result by denominator of the fraction: 162/5 = 32.4
Since 162/5 is an improper fraction, the result could also be expressed as a mixed number: 32 2/5
How does it work?
The principle behind finding a fraction of a number, such as 9/5 of 18, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 9/5 of 18)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 5 to isolate x:
- Which gives the result:
Thus, 9/5 of 18 is equal to 162/5 (or 32.4 in its decimal form).