Enumerables Exercise

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  1. Write a small program that asks for a number and it prints out “Hello!” to the user as many times as the number that was entered.

  2. Create an array with 5 numbers and multiply each numbers with 2 and return the result for each number in a new array.

  3. Here is an array with some names:

     names = ["John", "Angus", "Jane", "Hannibal"]

    Write some code to get all names which start with the letter J. The result should be stored in a new array.

  4. We have the following method:

     def mystery(numbers)
       numbers.select do |number|
         number % 3 == 0

    What does the method mystery return if we call it with…

     mystery([1, 5, 9, 11, 18])
  5. Write a method which takes an array of numbers as argument and returns the first number that can be divided by 5