Question

What is the greatest number which when divides $398$ and $436$, leaves $7$ and $11$ respectively as remainders?

Answer 1

This means, we have to find the HCF of $398-7=391$ and $436-11=425$
Factors of $391=1,17,23,291$

Factors of $425=1,5,17,25,85,425$

Common factors are $=1,17$

=> HCF $=17$