What is 4/9 of 42?

How to calculate 4/9 of 42?

1. Multiply the whole number by the numerator of the fraction: 42 × 4 = 168
2. Divide this result by denominator of the fraction: 168/9 = 18.666666666667
3. Simplify by dividing both the numerator and denominator by their GCD (3):
   • 168/3 = 56
   • 9/3 = 3
4. Which gives: 56/3

Since 56/3 is an improper fraction, the result could also be expressed as a mixed number: 18 2/3

How does it work?

The principle behind finding a fraction of a number, such as 4/9 of 42, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{4}{9}=\frac{x}{42}$ (where x represents 4/9 of 42)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $4\times 42=9x$
2. Which gives: $168=9x$
3. Divide both sides by 9 to isolate x: $\frac{168}{9}=\frac{9x}{9}$
4. Which gives the result: $\frac{168}{9}=x$ (or $\frac{56}{3}=x$)

Thus, 4/9 of 42 is equal to 56/3 (or 18.666666666667 in its decimal form).