What is 4/1 of 30?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 4/1 of 30? We'll show you a straightforward method to achieve that.
How to calculate 4/1 of 30?
- Multiply the whole number by the numerator of the fraction: 30 × 4 = 120
- Divide this result by denominator of the fraction: 120/1 = 120
How does it work?
The principle behind finding a fraction of a number, such as 4/1 of 30, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 4/1 of 30)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 1 to isolate x:
- Which gives the result:
Thus, 4/1 of 30 is equal to 120/1 (or 120 in its decimal form).