cashAmount

class CashAmount{
    constructor(amount) {
        this.amount = amount;
        this.pennies = this.amount * 100; 
    }
   
    addDoubleAmount (newAdd) {
        this.amount += newAdd;
        this.pennies += newAdd*100;
    }
     toPennies () {
        return this.pennies;
    }
    toDouble() {
        return this.amount;
    }
    toDoubleString() {
        return this.amount.toString();
    }
    quantityOfEachDenomination() {
       var den = {};
       this.pennies % 100;
    }
    
};

const cash = new CashAmount(0.10);
cash.addDoubleAmount(0.20);

cash.toPennies();