freeCodeCamp/curriculum/challenges/english/06-quality-assurance/quality-assurance-and-testing-with-chai/test-if-a-value-falls-within-a-specific-range.md

---
id: 587d824c367417b2b2512c4f
title: Test if a Value Falls within a Specific Range
challengeType: 2
forumTopicId: 301598
dashedName: test-if-a-value-falls-within-a-specific-range
---

# --description--

As a reminder, this project is being built upon the following starter project on [Replit](https://replit.com/github/freeCodeCamp/boilerplate-mochachai), or cloned from [GitHub](https://github.com/freeCodeCamp/boilerplate-mochachai/).

```javascript
.approximately(actual, expected, delta, [message])
```

Asserts that the `actual` is equal to `expected`, to within a +/- `delta` range.

# --instructions--

Within `tests/1_unit-tests.js` under the test labelled `#10` in the `Comparisons` suite, change each `assert` to `assert.approximately` to make the test pass (should evaluate to `true`).

Choose the minimum range (3rd parameter) to make the test always pass. It should be less than 1.

# --hints--

All tests should pass.

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=9').then(
    (data) => {
      assert.equal(data.state, 'passed');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

You should choose the correct range for the first assertion - `approximately(actual, expected, range)`.

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=9').then(
    (data) => {
      assert.equal(data.assertions[0].method, 'approximately');
      assert.equal(
        data.assertions[0].args[2],
        0.5,
        "weirdNumbers(0.5) is in the range (0.5, 1.5]. It's within 1 +/- 0.5"
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

You should choose the correct range for the second assertion - `approximately(actual, expected, range)`.

```js
(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=9').then(
    (data) => {
      assert.equal(data.assertions[1].method, 'approximately');
      assert.equal(
        data.assertions[1].args[2],
        0.8,
        "weirdNumbers(0.2) is in the range (0.2, 1.2]. It's within 1 +/- 0.8"
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );
```

# --solutions--

```js
/**
  Backend challenges don't need solutions, 
  because they would need to be tested against a full working project. 
  Please check our contributing guidelines to learn more.
*/
```