Depends on the subject, but the admissions tutors would almost certainly not leave it at that. Student one might arrive at an answer, and then be told that in actuality, the time was different; the tutor might then ask them to come up with an explanation for why the times were different.
Student two might be asked to consider how a shop could put a recommended cooking time on all of its turkeys, given that there are a number of variables, before being asked to consider the merits of generalising results of experiment into theories.
Student three would probably then be set another condition that they are home alone, and the telephone/internet router is broken.
This reminds me of a story of a student pilot flying at night, when the instructor turns off all the lights, saying to the student: "your lighting's broken - what do you do?". The student pulls a torch out of their pocket, and says "I use my torch!". The instructor grabs the torch, says "your batteries are flat - what do you do?"; the student pulls out another torch, and says "I use my other torch!". The instructor grabs the torch, declares its bulb broken, and the student pulls out a third torch. At this point, the instructor tells the student that all of their torches are broken, and asks them what they would do.
The student declares, "I'll use this glowstick!".
The point I'm making is that there are multiple ways to solve one problem, and it is this ability that Oxbridge tutors tend to look for, as it give evidence of independent thought. They're not looking for people to regurgitate the thoughts and statements of others, they're looking for originality. Oxford want "independent thinkers", and as such aren't looking for a student who answers a question in a specific way. Far more important is the ability of the student to think through the problem and find a solution, whatever it may be.