Answer: 0.75
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Step-by-step explanation:
You'll look at each four digit group separately.
Since we want more than 2 people having a pet, this means the group of four must have 3 pet owners or all 4 are pet owners.
The digit 5 represents "no pet". If we see it show up twice or more, then we must cross the group off the list. Something like 5533 has the first two people that don't own pets, while the last two people do own pets. In this case, we don't have a "more than 2 pet owners" situation happening. So we must cross it off the list.
Here is the list of groups to cross off
There are five such groups we have eliminated. That leaves 20-5 = 15 groups where there are more than 2 pet owners.
We have 15 groups we want out of 20 total. It leads to the probability of 15/20 = 0.75