What is 1/7 of 91?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 1/7 of 91? We'll show you a straightforward method to achieve that.
How to calculate 1/7 of 91?
- Multiply the whole number by the numerator of the fraction: 91 × 1 = 91
- Divide this result by denominator of the fraction: 91/7 = 13
- Simplify by dividing both the numerator and denominator by their GCD (7):
- 91/7 = 13
- 7/7 = 1
- Which gives: 13/1
How does it work?
The principle behind finding a fraction of a number, such as 1/7 of 91, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 1/7 of 91)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 7 to isolate x:
- Which gives the result: (or )
Thus, 1/7 of 91 is equal to 13/1 (or 13 in its decimal form).