What is 7/8 of 28?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 7/8 of 28? We'll show you a straightforward method to achieve that.
How to calculate 7/8 of 28?
- Multiply the whole number by the numerator of the fraction: 28 × 7 = 196
- Divide this result by denominator of the fraction: 196/8 = 24.5
- Simplify by dividing both the numerator and denominator by their GCD (4):
- 196/4 = 49
- 8/4 = 2
- Which gives: 49/2
Since 49/2 is an improper fraction, the result could also be expressed as a mixed number: 24 1/2
How does it work?
The principle behind finding a fraction of a number, such as 7/8 of 28, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 7/8 of 28)
- 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, 7/8 of 28 is equal to 49/2 (or 24.5 in its decimal form).