Typescript "unrounding" number on simple calculation

Question

I'm facing a very strange "unrounding" issue with typescript.

I have an app using Angular 6 and ngrx/store, on which I have some products (stored as an array of objects in the store).

Each time user increment or decrement a product quantity, a corresponding action is dispatched to store, which updates product quantity and also the products total. My store state and reducer code for incrementing product quantity are shown bellow:

export interface State {
  products: Product[];
  total: number;
}

const initialState = {
  products: [],
  total: 0
};

export function productsReducer(state = initialState, action: ProductsActions) {
  let updatedProducts = [];
  let updatedTotal = 0;
  switch (action.type) {

    case INCREMENT_PRODUCT_QUANTITY:
      updatedProducts = [...state.products];
      updatedProducts[action.payload].quantity++;
      updatedTotal = state.total + updatedProducts[action.payload].price;
      return {
        ...state,
        products: updatedProducts,
        total: updatedTotal
      };
  }
}

So, I have a product for which the price is 214.20 and when increasing this product quantity, product total is being calculated as below:

1. First increment -> total = 214.20
2. Second increment -> total = 428.40
3. Third increment -> total = 642.5999999999999

The issue is that products total is being calculated as 642.5999999999999, while the expected correct result is 642.60

Inspecting the variable values, the following math is occurring: 428.40 + 214.20 = 642.5999999999999

Any idea on the cause of this issue and how to solve it?

Thanks in advance!