How would you solve this?
This would be my structure (for simplicity just focusing on one pyramid in Egypt)
Number of workers = workers in quarry + workers transporting stones from quarry to pyramid + workers actually building pyramid + other workers
workers in quarry
workers in quarry = required stones per day / required workers per stone per day
required stones per day = required stones total / time to build pyramid
required stones total = Volume Pyramid / Volume average stone
I would need to estimate
- Volume Pyramid
- Volume average stone
- time to build pyramid
- required workers per stone per day (this one is tricky, further breakdown??)
workers transporting stones from quarry to pyramid
they were using some kind of sleds to transport stones so
workers transporting stones = required sleds * workers per sled
required sleds = number of stones per sled per day * required stones per day
number of stones per sled per day = Max number of stones fitting on one sled * number of rides per sled per day
I would need to estimate
- Max number of stones fitting on one sled
- number of rides per sled per day
- workers per sled
All of them seem tricky and might require further breakdown.
workers actually building pyramid
workers actually building pyramid = required stones per day * required workers per stone
I would need to estimate
- required workers per stone (might requires further breakdown)
Other workers
e.g. planners, other logistics, food, maintenance, etc.
I would just use something like 10-15% of total workers to add.
I feel like this is quite complex even with the assumptions that Im making which could be broke down further. Am I overthinking? Do you like the structure?
Case was asked during an interview of a boutique consultancy and I dont know what additional infos they were providing during the case. I assume they helped a lot otherwise the case is to long / doesnt provide recruiters so much insights to justify time spend for this case.
thanks!
You are right, I would need to substract something from the Pyramid volume. Had this in mind but didnt wrote it down here for simplicity. Time to build is an educated guess, indeed. I dont see anyway to sove the case without guessing the time to build (maybe they would tell that number). More difficult to guess are some of the other sub-items (e.g. how many "workers" you need to produce one stone). Where is further breakdown required and where is it fine to guess?