Fraction prime factor LCM HCF etc.

Answer: HCF of fractions=HCF of numeratorsLCM of denominators,LCM of fractions=LCM of numeratorsHCF of denominators\text{HCF of fractions} = \frac{\text{HCF of numerators}}{\text{LCM of denominators}}, \quad \text{LCM of fractions} = \frac{\text{LCM of numerators}}{\text{HCF of denominators}}

Step-by-step solution

Step 1: State formulas for HCF and LCM of fractions

To find the HCF\text{HCF} and LCM\text{LCM} of fractions, all fractions must first be expressed in their simplest form. The HCF\text{HCF} of a set of fractions equals the HCF\text{HCF} of the numerators divided by the LCM\text{LCM} of the denominators. Similarly, the LCM\text{LCM} of fractions equals the LCM\text{LCM} of the numerators divided by the HCF\text{HCF} of the denominators.

Step 2: Set up an example and express terms in prime factor form

Let us consider an example with two fractions, 23\frac{2}{3} and 89\frac{8}{9}. We find the prime factorization of each numerator: 2=212 = 2^1 and 8=238 = 2^3. For the denominators, we have 3=313 = 3^1 and 9=329 = 3^2.

Step 3: Calculate the HCF of the fractions

The HCF\text{HCF} of the numerators 22 and 88 is the product of common prime factors with the smallest exponent, which gives 21=22^1 = 2. The LCM\text{LCM} of the denominators 33 and 99 is the product of the highest powers of each prime factor, which gives 32=93^2 = 9. Thus, the HCF\text{HCF} is 29\frac{2}{9}.

Step 4: Calculate the LCM of the fractions

The LCM\text{LCM} of the numerators 22 and 88 is 23=82^3 = 8. The HCF\text{HCF} of the denominators 33 and 99 is 31=33^1 = 3. Dividing the LCM\text{LCM} of the numerators by the HCF\text{HCF} of the denominators yields 83\frac{8}{3}.

Solve your own maths question free →