Shouldn’t I validate num to be an Integer?
p [1, 2, 3.4, 4, 5].collect { |number| number.is_a?(Integer) && number.even? }
[false, true, false, true, false]
Course: https://www.educative.io/collection/10370001/5658174447157248
Lesson: https://www.educative.io/collection/page/10370001/5658174447157248/5730161353818112