challenge project :finalGrade()

challenge.js

## Write a function, finalGrade(). It should:

take three arguments of type number
find the average of those three numbers
return the letter grade (as a string) that the average corresponds to
return ‘You have entered an invalid grade.’ if any of the three grades are less than 0 or greater than 100
0-59 should return: 'F'
60-69 should return: 'D'
70-79 should return: 'C'
80-89 should return: 'B'
90-100 should return: 'A'##





// solution ___ //


// Write your function here:
const finalGrade = (aA,bB,cC) => {
  if((aA < 0 || aA >100) || (bB < 0 || bB > 100) || (cC < 0 || cC > 100 ))
  {return'You have entered an invalid grade.';
  
  }
  let average = (aA + bB + cC) / 3
  if (average < 60){
    return 'F'
  }
  else if(average < 70){
    return 'D'
  }
  else if (average < 80 ){
    return 'C'
  }
  else if (average < 90){
    return 'B'
  }
  else if (average < 100){
    return 'A'
  }
};






// Uncomment the line below when you're ready to try out your function
console.log(finalGrade(99, 100, 95)) // Should print 'A'

// We encourage you to add more function calls of your own to test your code!