To service a single device in 12 seconds, 700 nanorobots are required, with all nanorobots working at the same constant rate. How many hours would it take for a single nanorobot to service 12 devices?
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Thanks for this one. I initially tried to do some ratio setup and got lost, then realized it's just a straight unit-rate problem once you break it down.
Same here, I overthought it at first too. Setting it up as robots × devices × time really simplifies things.
Wait, am I the only one who has to be careful with seconds vs hours here? I almost picked a choice that was in seconds.
Yeah the unit conversion is the whole trap in this question honestly.
Same trap got me. I had the right number and then converted wrong.
This felt more like a 605 level question. Once you set up the rate per nanorobot, it's pretty mechanical.
Can someone explain why we don't just multiply 12 seconds by 12 devices and be done? I know that's wrong but I can't articulate why.
Because the 700 robots are doing the work, not one. You have to account for the fact that a single robot is way slower.
Think of it as: one robot does 1/700 of the work in 12 seconds.
What it tests
Your ability to combine individual work rates, usually by working with the fraction of a job completed per unit of time.
Common trap
Adding the times instead of the rates, or forgetting to take the reciprocal when combining rates.