What is 9/5 of 90?
Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 9/5 of 90? We'll show you a straightforward method to achieve that.
How to calculate 9/5 of 90?
- Multiply the whole number by the numerator of the fraction: 90 × 9 = 810
- Divide this result by denominator of the fraction: 810/5 = 162
- Simplify by dividing both the numerator and denominator by their GCD (5):
- 810/5 = 162
- 5/5 = 1
- Which gives: 162/1
How does it work?
The principle behind finding a fraction of a number, such as 9/5 of 90, is rooted in the method of cross-multiplication.
Consider the following proportion: (where x represents 9/5 of 90)
- Using the cross-multiplication method, multiply both numerators by their opposite denominators:
- Which gives:
- Divide both sides by 5 to isolate x:
- Which gives the result: (or )
Thus, 9/5 of 90 is equal to 162/1 (or 162 in its decimal form).