const users = [
  {
    index: 0,
    isActive: false,
    balance: 2397.64,
    age: 39,
  },
  {
    index: 1,
    isActive: true,
    balance: 2608.48,
    age: 33,
  },
  {
    index: 2,
    isActive: true,
    balance: 1699.99,
    age: 25,
  },
];
//4)Reduce
const totalBalance = users.reduce((acc, user) => {
  console.log(acc, user);
}, 0); |