You were just getting into the office when you received a letter from Muffin that was labeled as “urgent”.
Meow! I want to go on vacation. They say that there is some delicious salmon in Irkutsk: I got so fed up with St. Petersburg fish.
Count how many bonus air miles I can get if I fly with MuffAir. My gut feeling as an avid discount hunter suggests that I can make a profit here.
The distance to Irkutsk is 4125 km. The number of air miles is 25% of this distance.
I’m waiting for the result!
For a start, let’s clarify what “air miles” are. These are bonuses from airlines that can be accumulated after each flight, and then these miles can be used to “pay” for a flight to a certain city. Bonus miles are accrued in different ways. In MuffAir, as we have already learned, bonuses constitute a percentage of the flight distance.
In our code, the distance is stored in variable distance, and the percentage is already converted to a fractional number and stored in variable percent.
These values are enough to get the right number of miles: multiply the distance by percentage.
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Fasten your seat belts</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/check-miles">2. Long-distance flight</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/kamchatka-miles">3. Going the second circle</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/first-function">4. Helper function</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/function-call">5. Function, I’m calling you!</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/parameter">6. I have a parameter for you</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/order-of-parameters">7. Order of parameters</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/return">8. Return from function</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/summary-1">9. Summary of “Functions”. Part 1</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/challenge-salary">10. Seventh program: “From salary to salary”</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/check-flight-class">11. Business trip</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/add-variables">12. Write, simplify</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/refactor-return">13. Get rid of unnecessary</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/optimization">14. Make me beautiful</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/add-percent">15. Just add percentage</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/calculate-flights">16. Call me quietly by name</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/add-miles-target">17. I see the target</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/flights-condition">18. How many flights?</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/flights-class-condition">19. Let’s clean up a little</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/which-is-faster">20. Who is faster?</a></li><li class="main-nav__course-contents-item"><a href="/courses/javascript-programming/functions/add-array">21. 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3.896.106.328.5.46.78.26.273.192.653.06.745-.26.735-2.66-1.6-5.728-3.766-7.16z" fill="#F1662A"/></svg></span><p class="course-loading-overlay__message"><b class="course-loading-overlay__message-title">Loading…</b><br><span class="course-loading-overlay__message-text">Everything will be ready in few seconds</span></p></div></div><div class="course-layout__sidebar course-theory"><div class="course-theory__inner course-theory__inner--left-stub"><button class="course-theory__close icon-close icon-close--light" type="button">Close</button><ul class="course-tabs course-tabs--non-interactive course-layout__theory-heading js--theory-tabs"><li class="course-tabs__item course-tabs__item--external course-tab course-tab--centered"><span class="course-tab__icon"><svg aria-hidden="true"><use xlink:href="/img/sprites/courses.svg#icon-theory"></use></svg></span><span class="course-tab__title">Theory</span></li><li class="course-tabs__item course-tabs__item--internal course-tab course-tab--centered course-tab--active js--theory-tab__theory"><span class="course-tab__icon"><svg aria-hidden="true"><use xlink:href="/img/sprites/courses.svg#icon-theory"></use></svg></span><span class="course-tab__title">Theory</span></li><li class="course-tabs__item course-tabs__item--internal course-tab course-tab--centered js--theory-tab__comments"><span class="course-tab__icon"><svg aria-hidden="true" style="width: 16px; height: 16px; fill: #2e2c9c;"><use xlink:href="/img/sprites/up.svg#comment"></use></svg></span><span class="course-tab__title">Comments</span></li></ul><section class="course-theory__content"><div class="js--theory-pane__theory course-theory__content-inner"><h1 class="course-theory__content-heading">Fasten your seat belts</h1><div class="course-theory__content-text"><p>You were just getting into the office when you received a letter from Muffin that was labeled as “urgent”.</p><blockquote><p>Meow! I want to go on vacation. They say that there is some delicious salmon in Irkutsk: I got so fed up with St. Petersburg fish.</p><p>Count how many bonus air miles I can get if I fly with MuffAir. My gut feeling as an avid discount hunter suggests that I can make a profit here.</p><p>The distance to Irkutsk is 4125 km. The number of air miles is 25% of this distance.</p><p>I’m waiting for the result!</p></blockquote><p>For a start, let’s clarify what “air miles” are. These are bonuses from airlines that can be accumulated after each flight, and then these miles can be used to “pay” for a flight to a certain city. Bonus miles are accrued in different ways. In MuffAir, as we have already learned, bonuses constitute a percentage of the flight distance.</p><p>In our code, the distance is stored in variable <code>distance</code>, and the percentage is already converted to a fractional number and stored in variable <code>percent</code>.</p><p>These values are enough to get the right number of miles: multiply the distance by percentage.</p></div></div><div class="js--theory-pane__comments hidden course-theory__content-inner"><div class="course-theory__content-text"><h2 class="course-theory__content-heading">Comments</h2><div id="disqus_thread"></div><script>
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var distance = 4125;
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Run</button></div><div class="course-browser__content"><div class="console js--console"><h2 class="sr-only">Result</h2><div class="console__content js--console__content"></div></div></div><div class="course-goals js--goals"><div class="course-goals__heading"><span class="course-goals__heading-title"><span class="course-goals__count-label">Goals</span><span class="course-goals__count">completed</span></span><button class="course-goals__button course-goals__button--expand js--goals__expand" type="button"><svg aria-hidden="true"><use xlink:href="/img/sprites/courses.svg#icon-collapse"></use></svg></button><a class="course-goals__button course-goals__button--next button button--green button--without-border hidden" href="/courses/javascript-programming/functions/check-miles" title="Long-distance flight"><svg aria-hidden="true"><use xlink:href="/img/sprites/courses.svg#arrow-white--mini"></use></svg></a></div><div class="course-goals__content"><ol class="course-goals__list"><li class="course-goals__list-item">Calculate the number of miles using formula <code>distance * percent</code> and write the result to variable <code>miles</code><span class="mark">.</span></li><li class="course-goals__list-item">Log the result in the console: <code>console.log('We’ll get ' + miles + ' miles for the flight to Irkutsk');</code><span class="mark">.</span></li></ol></div></div></div></div></article></div><div class="course-interface__overlay course-interface__overlay--active"></div></main><script
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