balance.js

const users = [
    {
      name: "Salvio",
      income: [115.3, 48.7, 98.3, 14.5],
      outgoing: [85.3, 13.5, 19.9]
    },
    {
      name: "Marcio",
      income: [24.6, 214.3, 45.3],
      outgoing: [185.3, 12.1, 120.0]
    },
    {
      name: "Lucia",
      income: [9.8, 120.3, 340.2, 45.3],
      outgoing: [450.2, 29.9]
    }
  ];

    function calculateBalance(income, outgoing) {
       const sumIncome = sumNumbers(income)
       const sumOutgoing = sumNumbers(outgoing)
       
       return sumIncome - sumOutgoing
    }

    function sumNumbers(numbers) {
        let sum = 0
        for (let number of numbers) {
            sum = sum + number
        } return sum
    }
    for (let user of users) {
        const balance = calculateBalance(user.income, user.outgoing)
        if (balance > 0) {
            console.log(`${user.name} has a positive balance of ${balance.toFixed(2)}`)
        } else {
            console.log(`${user.name} has a negative balance of ${balance.toFixed(2)} `)
        }
    }