A couple lives in a house with their sons and daughters and no one else. The couple has four sons and each of the sons has exactly two sisters. How many persons live in that house?
8
House Riddle Solution
Let's break down this logic puzzle step by step to figure out how many people live in the house.
Counting the Family Members
The question states that a couple lives in the house, along with their sons and daughters, and no one else. We need to count each group:
- The Couple: A couple consists of two people, a husband and a wife. So, that's 2 persons.
- The Sons: The question explicitly states they have four sons. So, that's 4 persons.
- The Daughters: This is where the key clue is located. It says that "each of the sons has exactly two sisters". This means that all four sons share the same set of sisters. If there were more than two daughters, each son would have more than two sisters. If there were fewer than two daughters (like one), each son would have only one sister. The only way for every single son to have exactly two sisters is if there are exactly two daughters in the family. So, that's 2 persons.
Total Number of Persons
Now we just need to add up the number of people in each group:
Total persons = Number of people in couple + Number of sons + Number of daughters
Total persons = 2 + 4 + 2 = 8
Therefore, a total of 8 persons live in that house.
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