[Solved] Why JavaScript Math.random() returns same number multiple times

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Random numbers can appear in streaks; that’s part of being random. But over time the law of large numbers should take over and even out those streaks. You can test that easily enough by running this a bunch of times and counting:

var numbers = Array(523,3452);
let counts = [0,0]

for (let i = 0; i < 10000; i++) {
    let choice = numbers[Math.floor(Math.random()*numbers.length)];
    if (choice ===  523) counts[0]++
    else if (choice == 3452) counts[1]++
}

// counts should be about even
console.log(counts);

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solved Why JavaScript Math.random() returns same number multiple times