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S4 ICT Cloud and IoT: Paper 3 Cost and Endurance
S4 ICT Cloud and IoT: Paper 3 Cost and Endurance
This paper is a combined workout: hours from a sampling interval, a year of storage from reading size, cost per GB and upload time, then address share, edge latency and battery life, a comparison of two plans per GB, and a correction where the divisor was flipped.
Direct answers Items 01 to 03 cover data volume and cost, 04 to 06 cover upload, address share and latency, 07 to 09 are endurance, plan comparison and multi-node volume, and 10 corrects a wrong answer.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S4 ICT Cloud Computing and IoT |
| Level | S4 |
02 Questions (10 items)
- FoundationA sensor logs 864,000 readings a day at 100 ms intervals. How many hours of sampling is that?
- FoundationEach reading is 512 bytes and there are 864,000 readings a day. What is one year of 365 days in GB?
- FoundationA 4 TB cloud plan costs 1,200 dollars a year. What is the cost per GB to three decimals?
- IntermediateHow long does a 1.5 GB upload take at 20 MB per second?
- IntermediateThe IPv4 space holds 4,294,967,296 addresses. What percentage do 50,000 devices use?
- IntermediateA check drops from 120 ms in the cloud to 8 ms at the edge. What percentage of latency is saved?
- ChallengeA 2000 mAh battery drains 1.2 mAh per transmission every 30 seconds. How many transmissions and hours?
- ChallengePlan A is 100 GB for 80 dollars a month; plan B is 1 TB for 600 dollars. Which is cheaper per GB, and by how much?
- ChallengeThree sensors each produce 720 readings per minute. How many readings in a day?
- Error redoA student turned a 1,200 dollar 4 TB plan into 3.41 dollars per GB. What went wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 24 hours | 864,000 times 0.1 second is 86,400 seconds, which is 24 hours. |
| 2 | About 150.4 GB | A day is 421.875 MB, so 365 days come to about 150.4 GB. |
| 3 | About 0.293 dollars per GB | 4 TB is 4096 GB, and 1200 divided by 4096 is about 0.293. |
| 4 | 76.8 seconds | 1.5 GB is 1536 MB, and 1536 divided by 20 is 76.8 seconds. |
| 5 | About 0.0012 percent | 50,000 divided by the address space is about 0.0012 percent. |
| 6 | About 93.3 percent | 112 ms out of 120 ms is about 93.3 percent saved. |
| 7 | About 1666 transmissions, about 13.9 hours | 2000 divided by 1.2 is about 1666, and 1666 times 30 seconds is about 13.9 hours. |
| 8 | Plan B, by about 0.214 dollars per GB | A costs 0.8 per GB and B about 0.586, a gap of about 0.214. |
| 9 | 3,110,400 readings | 3 times 720 times 1440 gives 3,110,400 readings. |
| 10 | He swapped divisor and dividend; the cost is about 0.293 dollars per GB | The cost is 1200 divided by 4096, not the other way round. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
S4 ICT cloud and IoT paper 3: ten answered items on yearly volume, cost per GB, latency savings and battery life.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.