What is 1/8 of 40?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 1/8 of 40? We'll show you a straightforward method to achieve that.
How to calculate 1/8 of 40?
- Multiply the whole number by the numerator of the fraction: 40 × 1 = 40
- Divide this result by denominator of the fraction: 40/8 = 5
- Simplify by dividing both the numerator and denominator by their GCD (8):
- 40/8 = 5
- 8/8 = 1
- Which gives: 5/1
How does it work?
The principle behind finding a fraction of a number, such as 1/8 of 40, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 1/8 of 40)
- 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, 1/8 of 40 is equal to 5/1 (or 5 in its decimal form).