What is 3/9 of 42?

How to calculate 3/9 of 42?

1. Multiply the whole number by the numerator of the fraction: 42 × 3 = 126
2. Divide this result by denominator of the fraction: 126/9 = 14
3. Simplify by dividing both the numerator and denominator by their GCD (9):
   • 126/9 = 14
   • 9/9 = 1
4. Which gives: 14/1

How does it work?

The principle behind finding a fraction of a number, such as 3/9 of 42, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{3}{9}=\frac{x}{42}$ (where x represents 3/9 of 42)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $3\times 42=9x$
2. Which gives: $126=9x$
3. Divide both sides by 9 to isolate x: $\frac{126}{9}=\frac{9x}{9}$
4. Which gives the result: $\frac{126}{9}=x$ (or $\frac{14}{1}=x$)

Thus, 3/9 of 42 is equal to 14/1 (or 14 in its decimal form).