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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Finishing the Calculator

Posted by Andrew Alvarez
Andrew Alvarez
11,964 Points

Challenge Task 1 of 3 Implement the subtract method.

Challenge Task 1 of 3

Implement the subtract method.

don't know what to do

can you also help me with multiply and divide?

calculator.js 
var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  },
  subtract: function(value) {
   this.subtract -= value;
  },
  multiply: function(value) {

  },
  divide: function(value) {

  },
  clear: function() {
    this.sum = 0;
  }, 
  equals: function() {
    return this.sum;
  }
}

1 Answer

Rich Bagley
Rich Bagley
25,869 Points

Hi Andrew,

This is really similar to the add method but you will need to replace the + with -, so:

subtract: function(value) {
    this.sum -= value;
  },

Using the same logic, the multiply character is * and the divide character is /.

Hope that helps :)

-Rich

Chinto Kaliya
Chinto Kaliya
73 Points

Why same logic for multiplication and division please explain