The HCF of $$\frac{1}{3} ,\frac{3}{4} ,\frac{4}{5},\frac{ 5}{6 }$$​and $$\frac{6}{7}$$​ is:

Correct option is A

Given:

$$\frac{1}{3} ,\frac{3}{4} ,\frac{4}{5},\frac{ 5}{6 }$$​​and $$\frac{6}{7}$$ 

Concept Used:
HCF of fractions=HCF of the numerators/ LCM of the denominators
Solution:
Numerators: 1,3,4,5,6
Denominators: 3,4,5,6,7
HCF of the numerators
1,3,4,5,6
The HCF of 1,3,4,5,6 is 1 (since 1 is the only number that divides all of them).
LCM of the denominators
3,4,5,6,7
The LCM of 3,4,5,6, is 420
HCF of fractions= $$\frac{HCF \ of \ the \ numerators} {LCM \ of \ the \ denominators} =\frac{ 1}{420}$$​​