Final answer:
The riddle's answer is that Mr. Smith has 5 kids in total: 1 boy and 4 girls. The riddle may appear to suggest that he has 20 children, but each daughter sharing the same four brothers is the key to the answer.
Step-by-step explanation:
The answer to the riddle: 'Mr. Smith had 4 daughters. Each daughter had 4 brothers.' is 5 children. Many often mistakenly interpret the riddle as each daughter having 4 individual brothers which would total for 16 brothers. However, the riddle essentially states that each daughter has the same 4 brothers. Hence, Mr. Smith has 4 daughters and 4 sons, which makes it a total of 5 different children.
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