# Conversion to number in JavaScript

Let's consider the following code:

`let a = '2'; let b = '3'; alert(a + b); // shows '23'`

As you can see, in our case, both variables contain strings, and respectively, they add up like strings.

Suppose, we would like the values of our variables in this case to be added not as strings, but as numbers. In this case, we can force our variable type to be converted to a number using the special function `Number`:

`let a = '2'; let b = '3'; alert(Number(a) + Number(b)); // shows 5`

You can convert strings to numbers not with the addition operation, but immediately when writing to a variable. This will work:

`let a = Number('2'); // the number 2 will be written to the variable let b = Number('3'); // the number 3 will be written to the variable alert(a + b); // shows 5`

Given a variable `a` with the value `'10'` and a variable `b` with the value `'20'`. Add the given variables as numbers.

Without running the code, determine what will be displayed on the screen:

`alert( Number('2') + Number('3') );`

Without running the code, determine what will be displayed on the screen:

`alert( 2 + Number('3') );`

Without running the code, determine what will be displayed on the screen:

`alert( '2' + Number('3') );`
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