Problem 5

2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.

What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?

Solution

# 2520 is the smallest number that can be

# divided by each of the numbers from 1 to 10

# without any remainder.

 

# What is the smallest positive number

# that is evenly divisible by all of the

# numbers from 1 to 20?

 

#I had to shorten this to fit on the blog

#correctly so

#r = result

#e = element

answer = [16,9,5,7,11,13,17,19].inject(1) {|r, e| r * e }

puts answer

 

Discussion

Well, that was easy.  I really enjoy inject style methods for operating on arrays..

If you have questions, leave a comment or please find me on Twitter (@azzlsoft) or email (rich@azzlsoft.com).