What is 4/8 of 19?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 4/8 of 19? We'll show you a straightforward method to achieve that.
How to calculate 4/8 of 19?
- Multiply the whole number by the numerator of the fraction: 19 × 4 = 76
- Divide this result by denominator of the fraction: 76/8 = 9.5
- Simplify by dividing both the numerator and denominator by their GCD (4):
- 76/4 = 19
- 8/4 = 2
- Which gives: 19/2
Since 19/2 is an improper fraction, the result could also be expressed as a mixed number: 9 1/2
How does it work?
The principle behind finding a fraction of a number, such as 4/8 of 19, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 4/8 of 19)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 8 to isolate x:
- Which gives the result: (or )
Thus, 4/8 of 19 is equal to 19/2 (or 9.5 in its decimal form).