Sum of Multiples

by Scott Currell

JavaScript

/**
  * Write function "findSum()"
  * 
  * findSum() will return the sum of all multiples of 3 and 5.
  *
  * For example:
  *
  * findSum(5) should return 8 (3 + 5);
  * findSum(10) should return 33 (3 + 5 + 6 + 9 + 10);
  */
  
  function findSum( n ) {
  	var sum = 0;
    
  	for( var i = 1; i <= n; i++ ) {
      if( i % 3 === 0 ) {
        sum += i;
      } else if( i % 5 === 0 ) {
        sum += i;
      }
    }
    
    console.log( sum );
  };
  
  findSum( 15 );