--- id: 63507c19151201368ee3e16c title: Step 4 challengeType: 0 dashedName: step-4 --- # --description-- The value of an input element is always a string, even if the input type is `number`. You need to convert this array of strings into an array of numbers. To do this, you can use the `.map()` method. Create a `numbers` variable and assign it the value of `array.map()`. Remember that `.map()` creates a new array, instead of mutating the original array. # --hints-- Your `calculate` function should have a `numbers` variable. ```js assert.match(calculate.toString(), /numbers/); ``` You should use the `.map()` method on your `array` variable. ```js assert.match(calculate.toString(), /array\.map\(\s*\)/); ``` You should assign the result of your `.map()` call to your `numbers` variable. ```js assert.match(calculate.toString(), /numbers\s*=\s*array\.map()/); ``` # --seed-- ## --seed-contents-- ```html Statistics Calculator

Statistics Calculator

Enter a list of comma-separated numbers.

The mean of a list of numbers is the average, calculated by taking the sum of all numbers and dividing that by the count of numbers.

Mean:

The median of a list of numbers is the number that appears in the middle of the list, when sorted from least to greatest.

Median:

The mode of a list of numbers is the number that appears most often in the list.

Mode:

The range of a list of numbers is the difference between the largest and smallest numbers in the list.

Range:

The variance of a list of numbers measures how far the values are from the mean, on average.

Variance:

The standard deviation of a list of numbers is the square root of the variance.

Standard Deviation:

``` ```css body { margin: 0; background-color: rgb(27, 27, 50); text-align: center; color: #fff; } button { cursor: pointer; background-color: rgb(59, 59, 79); border: 3px solid white; color: white; } input { background-color: rgb(10, 10, 35); color: white; border: 1px solid rgb(59, 59, 79); } .bold { font-weight: bold; } ``` ```js --fcc-editable-region-- const calculate = () => { const value = document.querySelector("#numbers").value; const array = value.split(/,\s*/g); } --fcc-editable-region-- ```