What is 2/3 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 2/3 of 18? We'll show you a straightforward method to achieve that.
How to calculate 2/3 of 18?
- Multiply the whole number by the numerator of the fraction: 18 × 2 = 36
- Divide this result by denominator of the fraction: 36/3 = 12
- Simplify by dividing both the numerator and denominator by their GCD (3):
- 36/3 = 12
- 3/3 = 1
- Which gives: 12/1
How does it work?
The principle behind finding a fraction of a number, such as 2/3 of 18, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 2/3 of 18)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 3 to isolate x:
- Which gives the result: (or )
Thus, 2/3 of 18 is equal to 12/1 (or 12 in its decimal form).