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                <!DOCTYPE html>
<html lang="en">

  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Calculator Project</title>
  <link rel="stylesheet" href="">
  <link rel="stylesheet" href="calculator.css">

  <div class="container mt-5">
    <h1>Simple Javascript Calculator </h1>
    <div class="row text-center">
      <div class="col-xs-12">
          <div class="form-inline">
            <input type="number" id="#num1" class="form-control m-3" placeholder="Number 1" />
            <select class="form-control  m-3" onchange="selectorValue()" id="operationSelector">
                            <option value="add">Plus</option>
                            <option value="minus">Minus</option>
                            <option value="divide">Divided By</option>
                            <option value="multiply">Multiplied By</option>
            <input type="number" id="#num2" class="form-control  m-3" placeholder="Number 2" />


    <div class="btn btn-primary" id="resultButton" onclick="calculate();">View Results</div>
    <div id="answer"></div>





                #answer {
    padding: 15px;
    margin-top: 25px;
    background: #fafafa;
    font-size: 24px;
    font-weight: bold;
    text-align: center;


function calculate() {  //declare function
    // get number values and convert strings to numbers
    var numberOne = Number(document.getElementById('#num1').value);
    var numberTwo = Number(document.getElementById('#num2').value);
    // select ids
    var resultButton = document.getElementById('#resultButton');
    optionValue = document.getElementById('operationSelector').value;
    if (optionValue == "add") {
        var selectedOperation = numberOne + numberTwo;
    } else if (optionValue == "minus") {
        var selectedOperation = numberOne - numberTwo;
    } else if (optionValue == "divide") {
        var selectedOperation = numberOne / numberTwo;
    } else {
        var selectedOperation = numberOne * numberTwo;

    return document.getElementById('answer').innerHTML = selectedOperation;