# Two numbers are in the ratio 4:5. Their highest common factor is 16. What is a pair of numbers that fits that?

Jan 29, 2017

The numbers are $64$ and $80$.
The two numbers are in the ratio $4 : 5$ and there is no common factor between $4$ and $5$ (i.e. highest common factor is $1$).
As the highest common factor of the two numbers is $16$,
the numbers are $4 \times 16$ and $5 \times 16$ i.e. $64$ and $80$.