Why is division in Ruby returning an integer instead of decimal value?

Question

For example:

9 / 5  #=> 1

but I expected 1.8. How can I get the correct decimal (non-integer) result? Why is it returning <

Answer 1

You can include the ruby mathn module.

require 'mathn'

This way, you are going to be able to make the division normally.

1/2              #=> (1/2)
(1/2) ** 3       #=> (1/8)
1/3*3            #=> 1
Math.sin(1/2)    #=> 0.479425538604203

This way, you get exact division (class Rational) until you decide to apply an operation that cannot be expressed as a rational, for example Math.sin.