Engage with knowledgeable experts and get accurate answers on IDNLearn.com. Our experts provide timely and accurate responses to help you navigate any topic or issue with confidence.

What is the least common denominator (LCD) for each group of fractions?

a. [tex]\(\frac{1}{6}\)[/tex] and [tex]\(\frac{7}{8}\)[/tex]
b. [tex]\(\frac{3}{4}\)[/tex] and [tex]\(\frac{7}{10}\)[/tex]
c. [tex]\(\frac{7}{12}, \frac{3}{8}\)[/tex], and [tex]\(\frac{11}{36}\)[/tex]
d. [tex]\(\frac{8}{15}, \frac{11}{30}\)[/tex], and [tex]\(\frac{3}{5}\)[/tex]


Sagot :

Sure, let's find the least common denominator (LCD) for each group of fractions step-by-step.

### Part a: [tex]\( \frac{1}{6} \)[/tex] and [tex]\( \frac{7}{8} \)[/tex]

To find the least common denominator for [tex]\( \frac{1}{6} \)[/tex] and [tex]\( \frac{7}{8} \)[/tex], we need to find the least common multiple (LCM) of the denominators 6 and 8.

The prime factorizations are:
- 6 = 2 × 3
- 8 = 2³

The LCM is found by taking the highest power of each prime that appears in the factorizations:
- Highest power of 2 is 2³ = 8
- Highest power of 3 is 3¹ = 3

Thus, the LCM of 6 and 8 is 8 × 3 = 24.

So, the least common denominator for [tex]\( \frac{1}{6} \)[/tex] and [tex]\( \frac{7}{8} \)[/tex] is 24.

### Part b: [tex]\( \frac{3}{4} \)[/tex] and [tex]\( \frac{7}{10} \)[/tex]

To find the least common denominator for [tex]\( \frac{3}{4} \)[/tex] and [tex]\( \frac{7}{10} \)[/tex], we need to find the LCM of the denominators 4 and 10.

The prime factorizations are:
- 4 = 2²
- 10 = 2 × 5

The LCM is:
- Highest power of 2 is 2² = 4
- Highest power of 5 is 5¹ = 5

Thus, the LCM of 4 and 10 is 4 × 5 = 20.

So, the least common denominator for [tex]\( \frac{3}{4} \)[/tex] and [tex]\( \frac{7}{10} \)[/tex] is 20.

### Part c: [tex]\( \frac{7}{12}, \frac{3}{8}, \)[/tex] and [tex]\( \frac{11}{36} \)[/tex]

To find the least common denominator for [tex]\( \frac{7}{12}, \frac{3}{8}, \)[/tex] and [tex]\( \frac{11}{36} \)[/tex], we need to find the LCM of the denominators 12, 8, and 36.

The prime factorizations are:
- 12 = 2² × 3
- 8 = 2³
- 36 = 2² × 3²

The LCM is:
- Highest power of 2 is 2³ = 8
- Highest power of 3 is 3² = 9

Thus, the LCM of 12, 8, and 36 is 8 × 9 = 72.

So, the least common denominator for [tex]\( \frac{7}{12}, \frac{3}{8}, \)[/tex] and [tex]\( \frac{11}{36} \)[/tex] is 72.

### Part d: [tex]\( \frac{8}{15}, \frac{11}{30}, \)[/tex] and [tex]\( \frac{3}{5} \)[/tex]

To find the least common denominator for [tex]\( \frac{8}{15}, \frac{11}{30}, \)[/tex] and [tex]\( \frac{3}{5} \)[/tex], we need to find the LCM of the denominators 15, 30, and 5.

The prime factorizations are:
- 15 = 3 × 5
- 30 = 2 × 3 × 5
- 5 = 5

The LCM is:
- Highest power of 2 is 2¹ = 2
- Highest power of 3 is 3¹ = 3
- Highest power of 5 is 5¹ = 5

Thus, the LCM of 15, 30, and 5 is 2 × 3 × 5 = 30.

So, the least common denominator for [tex]\( \frac{8}{15}, \frac{11}{30}, \)[/tex] and [tex]\( \frac{3}{5} \)[/tex] is 30.