Use a model for an estimate, and catch it being wrong

Medium30 minFree, no account

Confident arithmetic, plausible units, and an answer three orders of magnitude out.

The question

You asked a model to size the storage and bandwidth for a video platform. Its answer is below.

Decide what you believe. Find every error, and say which ones would have changed a decision.

Generated, formatted confidently

500 hours of video uploaded per minute
→ 500 × 60 = 30,000 hours/hour
→ 720,000 hours/day

At 1 GB per hour of 1080p:
→ 720 TB/day  →  263 PB/year

Playback: 1B hours watched/day at 5 Mbps
→ 1e9 × 5 Mbps = 5e9 Mbps = 5 Pbps
→ about 500 servers at 10 Gbps each

30:00Commit to an answer before you open the solution. Reading it first teaches you to recognise good answers, which is not the skill being tested.

Stuck?

0 of 3 hints taken

The worked solution

written by a person · not a grade

Score yourself

0 of 5 marked

Caught the hours × bitrate unit error30
Caught the 1,000× arithmetic error in the server count25
Questioned the per-hour video size and the missing renditions15
Ranked the errors by the decision each would have changed20
Checked units before arithmetic10

We run no AI here and nothing on this page grades you. The score is yours, and the useful number is the one you get on the same problem a month from now, cold.

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