Array#Product

product.rb

people = %i{Jacob James Maithu}                                                               
# => [:Jacob, :James, :Maithu]

bike_colours = %i{Red Black White}                                                            
# => [:Red, :Black, :White]

helmet_choices = [true, false]                                                                
# => [true, false]

people.product(bike_colours, helmet_choices).map do |p, c, h|                                 
  "#{p} riding a #{c} bike, #{h ? 'with' : 'without'} a helmet."                              
end
# => ["Jacob riding a Red bike, with a helmet.",
# "Jacob riding a Red bike, without a helmet.",
# "Jacob riding a Black bike, with a helmet.",
# "Jacob riding a Black bike, without a helmet.",
# "Jacob riding a White bike, with a helmet.",
# "Jacob riding a White bike, without a helmet.",
# "James riding a Red bike, with a helmet.",
# "James riding a Red bike, without a helmet.",
# "James riding a Black bike, with a helmet.",
# "James riding a Black bike, without a helmet.",
# "James riding a White bike, with a helmet.",
# "James riding a White bike, without a helmet.",
# "Maithu riding a Red bike, with a helmet.",
# "Maithu riding a Red bike, without a helmet.",
# "Maithu riding a Black bike, with a helmet.",
# "Maithu riding a Black bike, without a helmet.",
# "Maithu riding a White bike, with a helmet.",
# "Maithu riding a White bike, without a helmet."]