```Derek Perrault wrote:
> Modulus division = Remainder division
>
> Two goes into five two times, with one left over.   5 / 2  = 2 (R1).
> Modulus division only returns that remainder.  5 % 2 = 1
>
> Note that, when divided by 2, odd numbers always return 1, while even
> numbers always return 0.

okay, cool. i found the answer to the question on a forum online ...

def old_roman_number input

while input < 1 || input > 3999
puts 'Please enter a number between 1 and 3999'
input = gets.chomp.to_i
end

m_mod = input%1000
d_mod = input%500
c_mod = input%100
l_mod = input%50
x_mod = input%10
v_mod = input%5

m_div = input/1000
d_div = m_mod/500
c_div = d_mod/100
l_div = c_mod/50
x_div = l_mod/10
v_div = x_mod/5
i_div = v_mod/1

m = 'M' * m_div
d = 'D' * d_div
c = 'C' * c_div
l = 'L' * l_div
x = 'X' * x_div
v = 'V' * v_div
i = 'I' * i_div

puts m + d + c + l + x + v + i

end

number = gets.chomp.to_i
old_roman_number(number)

I understnad the first few lines .. the "while" stuff and and ending
stuff too. do you think you explain to me why the % and / works here? i
guess i really need to get better at math. i'm sorry if i'm being really
stupid here, hah. i just want to really understand things, not just see
and move on .. thank you again..

--
Posted via http://www.ruby-forum.com/.

```