What is 1/7 of 42?
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 42? We'll show you a straightforward method to achieve that.
How to calculate 1/7 of 42?
- Multiply the whole number by the numerator of the fraction: 42 × 1 = 42
- Divide this result by denominator of the fraction: 42/7 = 6
- Simplify by dividing both the numerator and denominator by their GCD (7):
- 42/7 = 6
- 7/7 = 1
- Which gives: 6/1
How does it work?
The principle behind finding a fraction of a number, such as 1/7 of 42, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 1/7 of 42)
- 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 42 is equal to 6/1 (or 6 in its decimal form).