Separation probability

I have the following code in PHP that works great (returns more or less 10 results every time it starts):

function GetAboutTenRandomNumbers()
{
    $result = array();

    for ($i = 0; $i < 240; $i++)
    {
        if (Chance(10, 240) === true)
        {
            $result[] = $i;
        }
    }

    echo '<pre>';
    print_r($result);
    echo '</pre>';

    return $result;
}

      

        
        
        
      

    

And the Chance () function looks like this:

function Chance($chance, $universe = 100)
{
    $chance = abs(intval($chance));
    $universe = abs(intval($universe));

    if (mt_rand(1, $universe) <= $chance)
    {
        return true;
    }

    return false;
}

      

        
        
        
      

    

Now I want to randomly split these 10 (average) results into the following 4 segments:

• the first has a probability of 10% * 10 = 1
• the second having a probability of 20% * 10 = 2
• third, with a probability of 30% * 10 = 3
• the fourth with a probability of 40% * 10 = 4

As you can see, the sum of all segments (1 + 2 + 3 + 4) is 10, so I have coded the following function for that.

function GetAboutTenWeightedRandomNumbers()
{
    $result = array();

    // Chance * 10%
    for ($i = 0; $i < 60; $i++)
    {
        if (Chance(10 * 0.1, 240) === true)
        {
            $result[] = $i;
        }
    }

    // Chance * 20%
    for ($i = 60; $i < 120; $i++)
    {
        if (Chance(10 * 0.2, 240) === true)
        {
            $result[] = $i;
        }
    }

    // Chance * 30%
    for ($i = 120; $i < 180; $i++)
    {
        if (Chance(10 * 0.3, 240) === true)
        {
            $result[] = $i;
        }
    }

    // Chance * 40%
    for ($i = 180; $i < 240; $i++)
    {
        if (Chance(10 * 0.4, 240) === true)
        {
            $result[] = $i;
        }
    }

    echo '<pre>';
    print_r($result);
    echo '</pre>';

    return $result;
}

      

        
        
        
      

    

The problem is that I have run the GetAboutTenWeightedRandomNumbers function dozens of times and the result is much lower than the result returned by the GetAboutTenRandomNumbers function. I'm sure I'm making a fundamental math mistake, I suspect where, but I don't know how to solve it.