Numbers To Know easy
For back-of-the-envelope estimations, what is a useful approximation for the number of seconds in a single day?
- A 86,400 (approximated as 100,000)
- B 3,600
- C 1,000,000
- D 10,000
Answer: A. 86,400 (approximated as 100,000)
Calculated exactly, there are $60 \times 60 \times 24 = 86,400$ seconds in one day. However, for quick system design math, it is standard to round this up to 100,000 ($10^5$). This estimation trick makes it much simpler to calculate daily throughput: for example, if a service receives 1 Million requests per day, you can instantly estimate its load as roughly 10 Requests Per Second (RPS) using $10^6 / 10^5 = 10$.
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