i need the technique......

Question

if 2 is the greatest number that divides evenly into both x and y,what is the greatest number that divides evenly into both 5x and 5y?

 options: 2,4,6,8

 

 

Answer 1

x and y are both divisible by 2

5x and 5y are both divisible by 5 and also both divisible by 2

if x and y are both divisible by 2 and both divisible by 5 then they are both divisible by 5*2=10

10 is the answer but is not listed