Question: Find the least common denominator (LCD) of $\frac{1}{10}$ and $\frac{8}{15}$.
1. **State the problem:** We need to find the least common denominator (LCD) of the fractions $\frac{1}{10}$ and $\frac{8}{15}$.
2. **Recall the formula:** The LCD of two fractions is the least common multiple (LCM) of their denominators. Here, the denominators are $10$ and $15$.
3. **Find the prime factorizations:**
- $10 = 2 \times 5$
- $15 = 3 \times 5$
4. **Find the LCM:**
The LCM is found by taking the highest powers of all prime factors appearing in either number.
- For $2$: highest power is $2^1$
- For $3$: highest power is $3^1$
- For $5$: highest power is $5^1$
So,
$$\text{LCM}(10, 15) = 2 \times 3 \times 5 = 30$$
5. **Conclusion:**
The least common denominator (LCD) of $\frac{1}{10}$ and $\frac{8}{15}$ is $30$.