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Writing a javascript function for codecademy

Taking some time to try and learn Javascript to become a better developer. I am having a bit of problem with this code.

function howOld (age, year) {
  let theCurrentYear = 2020;
  const yearDifference = year - theCurrentYear;
  const newAge = Math.abs(age + yearDifference);
  const positiveNewAge = newAge * -1;
  
  if (newAge > age) {
    return `You will be ${newAge} in the year ${year}`;
  } else if (newAge < 0) {
    return `The year ${year} was ${positiveNewAge} years before you were born`;
  } else if (newAge > 0 && newAge < age) {
    return `You were ${positiveNewAge} in the year ${year}`;
  }
};

console.log(howOld(28,2019));

Here is what it should do:

Write a function, howOld(), that has two number parameters, age and year, and returns how old someone who is currently that age was (or will be) during that year. Handle three different cases:

If the year is in the future, you should return a string in the following format:

'You will be [calculated age] in the year [year passed in]' If the year is before they were born, you should return a string in the following format:

'The year [year passed in] was [calculated number of years] years before you were born' If the year is in the past but not before the person was born, you should return a string in the following format:

'You were [calculated age] in the year [year passed in]'

The problem I am having is getting the newAge to be a positive number so I can pass it as a positive onto the string. I have tried Math.abs() and multiplying the newAge by -1 and I can't seem to get it to change to a positive number.

Thanks to @vlaz for making me try this again. Here is the answer I came up with after trying this again.

function howOld (age, year) {
  let theCurrentYear = 2020;
  const yearDifference = year - theCurrentYear;
  const newAge = age + yearDifference;
  const positiveNewAge = Math.abs(newAge);
  
  if (newAge > age) {
    return `You will be ${newAge} in the year ${year}`;
  } else if (newAge < 0) {
    return `The year ${year} was ${positiveNewAge} years before you were born`;
  } else if (newAge > 0 && newAge < age) {
    return `You were ${positiveNewAge} in the year ${year}`;
  } else if (year === theCurrentYear) {
    return `You are ${age} in the year ${2020}`;
  }
};

console.log(howOld(28,1991));

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