Theory is good, but without practice how to fly with one wing, so in this section we will solve problems in JavaScript. We took the tasks from the Codewars - site this is a site where you can improve your skills not only in JavaScript, but also in other programming languages.

## Find numbers that are divisible by a given number​

Complete a function that takes two arguments and returns all numbers that are divisible by the given divisor. The first argument is an array of numbers and the second is a divisor.

### Example​

``divisibleBy([1, 2, 3, 4, 5, 6], 2) == [2, 4, 6]``

### Practice​

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See the answer only if you could not solve the problem yourself.

## Twice as old​

• father's current age (years)
• the current age of the son (years)

Calculate how many years ago a father was twice as old as his son, or in how many years he will be twice as old.

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## Count odd numbers below `n`​

If number `n` is given, return the number of positive odd numbers less than `n`, EASY!

### Example​

``oddCount(7) //=> 3, i.e [1, 3, 5]oddCount(15) //=> 7, i.e [1, 3, 5, 7, 9, 11, 13]``

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## Convert string to number!​

We need a function that can convert a string to a number. What ways do you know to achieve this?

Note: Don't worry, all inputs will be strings, and each string is a perfectly valid integer representation.

### Example​

``stringToNumber('1234') == 1234stringToNumber('605') == 605stringToNumber('1405') == 1405stringToNumber('-7') == -7``

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