No since the between consecutive numbers doesn't give a constant
This looks confusing. Can you try reposting this to make it look clear?
X - $5 bills
y - $10 bills
x + y = 12
y = 5x
x + (5x) = 12
6x = 12
x = 2
y = 5(2)
y = 10
10 $10 bills and 2 $5 bills