#Exercise Grade

gradeEx.rb

=begin
Simple Grade exercise
=end

print "Enter your marks: "
grade = Integer(gets.chomp)

case grade
    when 90..100
        letter_grade = "A"
    when 80..90
        letter_grade = "B"
    when 70..80
        letter_grade = "C"
    when 60..70
        letter_grade = "D"
    else
        letter_grade = "F"
end

puts
print letter_grade