If there are 300 million numerical possibilities and you bought 5, then there are still 299,999,995 that you have not bought. Each of the tickets has that 1 in 300 million chance. That is additive, not multiplicative.
That is idiotic. You do not understand the math.
When you buy five tickets, you have a five out of 300,000,000 chance of winning.
That means you have a one out of 60,000,000 chance of winning.
It’s that simple, poet.