What is 5/10 of 78?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 5/10 of 78? We'll show you a straightforward method to achieve that.
How to calculate 5/10 of 78?
- Multiply the whole number by the numerator of the fraction: 78 × 5 = 390
- Divide this result by denominator of the fraction: 390/10 = 39
- Simplify by dividing both the numerator and denominator by their GCD (10):
- 390/10 = 39
- 10/10 = 1
- Which gives: 39/1
How does it work?
The principle behind finding a fraction of a number, such as 5/10 of 78, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 5/10 of 78)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 10 to isolate x:
- Which gives the result: (or )
Thus, 5/10 of 78 is equal to 39/1 (or 39 in its decimal form).