Sample problems 3: objects and arrays

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  <h1>Please look in the code below for 4 JavaScript practice problems.</h1>
  <p>(These problems don't include any SVG manipulation, so you will need to open the developer console in order to see the output of your code)</p>
  <script>

states = [{name: "Alaska", id: "AK", population: 741894},
            {name: "Virginia", id: "VA", population: 8411808},
    				{name: "Arizona", id: "AZ", population: 6931071},
            {name: "Florida", id: "FL", population: 20984400}]
            
  // Problem 1: using d3.mean(), compute and print the average (mean) 
  // population of the states in the states array
  
  var population_mean = d3.mean(states, function (i) {
    return i.population;
  });
    
  console.log("Solution 1:", population_mean);
  
  
  // Problem 2: WITHOUT using d3.mean(), compute and print the average (mean) 
  // population of the states in the states array

var average = 0;
    
    for (i = 0; i < states.length; i++){
      average += states[i].population;
    }
    
    average = average / states.length
    
    console.log("Solution 2:", average)
    
    //problem 3
    
    var population = 0;
    var mean = 0;
    var i = 0
   
    while ( i < states.length){
      population += states[i].population; i++
    }
    
    mean = population / states.length
    console.log("Solution 3:", mean)
    
  </script>
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https://d3js.org/d3.v4.min.js