What is 4/8 of 87?
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 87? We'll show you a straightforward method to achieve that.
How to calculate 4/8 of 87?
- Multiply the whole number by the numerator of the fraction: 87 × 4 = 348
- Divide this result by denominator of the fraction: 348/8 = 43.5
- Simplify by dividing both the numerator and denominator by their GCD (4):
- 348/4 = 87
- 8/4 = 2
- Which gives: 87/2
Since 87/2 is an improper fraction, the result could also be expressed as a mixed number: 43 1/2
How does it work?
The principle behind finding a fraction of a number, such as 4/8 of 87, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 4/8 of 87)
- 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 87 is equal to 87/2 (or 43.5 in its decimal form).