Setting up MIT Scheme on Ubuntu 18.04

I'm going through Structure and Interpretation of Computer Programs and for exercise 1.3 there is this question:

Exercise 1.3.  Define a procedure that takes three numbers as arguments and returns the sum of the squares of the two larger numbers. 

All the other questions for this section may be solved with pen and paper, but I think this one is easier to see when you code. First, let's install scheme on Ubuntu:

$ sudo apt install mit-scheme

Secondly, let's create a file max-three-sum-squares.scm with the following content:

(define (max-three-square x y z)
   ( cond
       ((and (> x z) (> y z)) (+(* x x)(* y y)))
       ((and (> x y) (> z y)) (+(* x x)(* z z)))
       ((and (> z x) (> y x)) (+(* z z)(* y y)))
   )
)
(display (max-three-square 3 4 5))
(display "\n")

To execute the program, we have to call the interpreter with the code, but requesting it not to display any debug information (hence the --quiet flag):

$ scheme --quiet < max-three-sum-squares.scm

That's it, you are now a little schemer.