Adding Fractions: Solve 1/4 + 1/9 Step by Step

Since 4 and 9 share no common factors (4 = 2² and 9 = 3²), their LCD is simply 4 × 9 = 36. For numbers with common factors, you'd need to find the LCM differently.

Fractions represent parts of different wholes! $\frac{1}{4}$ means 1 out of 4 pieces, while $\frac{1}{9}$ means 1 out of 9 pieces. You need the same-sized pieces before adding.

That would work too! $\frac{18}{72} + \frac{8}{72} = \frac{26}{72}$ which simplifies to $\frac{13}{36}$. But using the LCD saves work by avoiding extra simplification.

Check if the numerator and denominator have common factors. Since 13 is prime and doesn't divide 36, $\frac{13}{36}$ is already in lowest terms.

Yes, but be careful with rounding! $\frac{1}{4} = 0.25$ and $\frac{1}{9} ≈ 0.111...$ The exact answer $\frac{13}{36}$ is more precise than 0.361...