Hardest Cambridge Interview Questions and Answers

Oxbridge Application Specialists

Here, we present ten of the most challenging interview questions for Cambridge applicants. More specific questions can be found in our Oxbridge Interview Question Bank.

Cambridge Interview: Left-Field Questions

About 1 in 4 deaths in the UK is due to some form of cancer, yet in the Philippines the figure is only around 1 in 10. What factors might account for this difference?

I would break this question down into three parts. The first is lifestyle, the second lifespan, and the third natural selection. Considering lifestyle first, it should be apparent that in many Western countries the lifestyle is hugely conducive to cancer – high levels of drinking, obesity, and very little exercise being the norm. I would assume that levels of smoking are not dissimilar from the UK to the Philippines. This is the first reason that cancer deaths would be higher in the UK. Second is lifespan – put simply, healthcare in the UK will be good enough to help the average UK citizen survive until a relatively old age – by which point it is much more likely that they will suffer, and in turn die from, cancer. On the other hand, the Philippines will have inferior healthcare that is more likely to see people die from disease, increased childhood mortality, and thus lower rates of people suffering cancer. Lastly, I would question if some form of relaxation in natural selection in the West is happening, in which modern Medicine does allow certain people to survive cancers that would otherwise kill them, and in turn to pass the genes which caused those cancers on – increasing the proportion of the population who may suffer from cancer in the future. This is perhaps more speculative and would be part of a longer-term process away from natural selection in developed countries.


How would you simulate altitude in your living room?

I know that at altitude there is less oxygen in the air, as density decreases, increasing the space between molecules. Whilst this would be difficult to simulate, I could instead use the fact that nitrogen makes up the most-part of the air that we breathe. I would make a device that removes oxygen from the ambient air in the living room, and then releases nitrogen into the air in its place. This could be done in such a way as to perfectly imitate the decrease in oxygen molecules that one would expect at a higher altitude. 


Is pursuing happiness ethical?

This simply depends on one’s definition of ‘ethical.’ To pursue happiness would be hedonism – which is in and of itself a way of defining ethical actions. Hedonism asserts that an ethical action is one in which we maximise pleasure – the pursuit of happiness, or pleasure, is ‘good’. However, we must consider what ‘happiness’ is – which is another discussion. We might take the Epicurean view that pleasure is the absence of pain, for example – a simple approach which would contrast with what we typically think of as hedonism.

Question Bank

Techniques, Tutorials & Past Interview Scenarios With Example Answers

Private Tuition

One to One Support With An Oxbridge Interview Specialist. Optimise Your Preparation; Secure Your Offer.

Resources & Articles

Tips, Techniques & Insight from Oxbridge Interview Specialists & Past Successful Applicants

Cambridge Interview: Brain Teasers

What percentage of the world’s water is contained in a cow?

The actual answer here is that there are 1.3 billion cows on the planet, and that the percentage of all the world’s water contained in one cow is 0.000000001%.

I would say in an interview that I would first need to consider the number of cows on the planet. I would then want to consider the total volume of water on the planet. I would then need to consider the volume of water within a cow – that being a sum, primarily, of the interstitial fluid, the intracellular fluid, and the blood. I could perhaps estimate the fluid in the cow by assuming that roughly 70% of its weight might be fluid (similar to a human), and that a cow could weigh, roughly, 1000kg. That would mean a cow contains 700kg of fluid, which for the purposes of simplicity, we could say is 700L of water. I could perhaps assume that there are a set number of cows per person – given that milk is commonly drunk across the planet, there must be at least one cow to every ten people, perhaps. We could therefore say there might be roughly 1 billion cows on the planet. Estimating the amount of water on the planet is clearly very difficult, and I would hope at this point that an interviewer would step in and discuss the topic further with you. 

Would it matter if tigers became extinct?

We can approach this from two directions – an ethical or moral one, and a purely biological or utilitarian one. From a utilitarian perspective, the extinction of tigers would have little impact on the destiny of the planet or of humankind – and humankind are currently the sole beings who are able to decide on what ‘matters’ and what does not. Tigers are apex predators, and therefore would have little impact on the wider ecosystem – it is unlikely that the population of the secondary consumers below them would spiral out of control in today’s world. It is safe to assume that tigers becoming extinct would not have a material impact. However, it would matter from a moral and ethical standpoint. The reason for tigers becoming extinct would be simple – human activity. A majestic species found throughout our stories and histories from millennia, that walked the earth for millennia before, ought to be safeguarded. Such a species can inspire emotion and impact the world in intangible ways. It is therefore our duty to prevent such a species becoming extinct and lost forever.


Ladybirds are red. So are strawberries. Why?

The paradox here seems to be that one wants to be eaten – the strawberry – and one does not – the ladybird. The strawberry would benefit from being eaten as this will allow it to be seeded elsewhere and in turn for strawberry plants to grow across a wider area. On the other hand, the ladybird needs to avoid predation in order to succeed. I can only therefore assume that the colour red signals different things to different animals. To herbivores that might eat a strawberry, it must indicate that the food is safe to eat, whereas for a small carnivore or a bird that might eat a ladybird, it must indicate risk, and that the animal is unsafe to eat.


Oxbridge Interview Services

Tailor and optimise your Interview Preparation with our 1-1 Oxbridge Interview Specialists or prepare in your own time with our Online Oxbridge Interview Course & Question Bank

Cambridge Interview: Humanity, Thought & You

If you had to give human rights to one of either chimpanzees, dogs or elephants, which would you choose?

Our human rights are a set of basic and inviolable rights which every human ought to have – like education, liberty, freedom of thought, the right to life, or the right of freedom of expression. We should therefore consider the rights, or what we know of them, and which animal is most likely to benefit from them. Chimpanzees are the most intelligent of the listed animals, and the most human-like, meaning that they would make a reflexive first choice for many asked this question. Dogs, on the other hand, are humans’ loyal companions – they have accompanied us through millennia and are widely held to be part of our journey to becoming much better hunters, and in turn to succeeding as a species. Perhaps they ought to be rewarded with human rights? Certainly they are loyal, trustworthy, and have shown that they can benefit from education. That said, would the right to freedom of expression or freedom of thought be of huge use to the typical dog? Probably not. Finally, elephants have a great intelligence, and a great emotional intelligence too. They live long lives, have families, and show grief in very human ways.

I would argue that elephants would benefit most from human rights – but not for the reasons listed above. Instead, I would focus on the fact that dogs already have a special place; they thrive alongside humans. Chimpanzees are endangered. However, elephants are far more endangered even than chimpanzees. I would therefore give human rights to elephants simply, or ironically, to protect them from humans – to prevent them becoming even more endangered. 


How does the way you think determine who you are?

Arguably, the way you think could entirely determine who you are. We would need to first define what we mean by ‘who we are.’ Is this how we perceive ourselves, or how others perceive us? If it is only how we perceive ourselves – something of a more solipsistic viewpoint perhaps, in which we are the only true meaning – then how we think is the sole determinant of who we are.

If who we are is determined by others, then our thoughts will have something less of an effect. Others’ perception of us may be determined already by how we look, or things that they have heard about us, and our identity – who we are – will be a function of these functions, rather than our true thoughts and the way in which we think. It is more likely, however, that our thoughts and beliefs will still define us – through our personality, the views that we express, etc. Whether famous or known by next to no-one, our manner of thinking will still be evident and be a huge part of how people perceive us, describe us to others, and thus who we are in a wider sense.

Can we think without language?

We should break this down into two questions – can we think without language, and can we reason or think through more complex situations without language? Clearly, ‘thinking’ without language is possible. A cat thinks, as it chases a mouse and predicts where the mouse will go next. Yet a cat has no language. Humans must think from their earliest days – babies and very young children without the facility of language still can clearly emote and display feelings and actions that are the result of thought processes. Whether we can think through more complex thoughts without language is a different question – can we conceptualise without language? I believe that this is much more difficult. If we imagine a deaf person who has never been communicated with in a recognisable language – as no doubt would have happened in the past – they must still have been able to think. However, without clear language their thought processes would have been different. It would still be possible for someone to think ‘the majority of elephants must be grey’ without language, as they would presumably visualise elephants, a number of elephants, and then the elephants being grey. However, trying to answer a question like ‘is the declaration of independence still relevant’ would be rather more difficult – how does one picture relevance? Would one have a concept of relevance without it ever having been communicated? I would assume that in such a situation our ability to think would be reduced, although we would perhaps develop workarounds – concepts or even a sort of internal language that allowed one to nurture more complex thoughts. I would therefore conclude that thought without language is possible but would not be as rich or as productive as thought with the benefit of a language that has evolved to serve us and allow us to think.

How would you go about learning 50 words a day?

I would approach this problem from two angles – firstly, I would need to schedule and organise the words that are to be learnt. Secondly, I would need to learn them efficiently. In terms of the schedule and organisation, I would ensure that I had a number of short periods throughout the day dedicated to the learning of new words, and that I had a clear structure as to the words that I wanted to learn. I would want to have set groups of words that made sense when taken together, and that would allow me to better understand particular topics or ideas therefore. This would allow me to be more interested in the learning I was doing, as I could more readily apply it. In terms of efficient learning, I would want to ensure that I could move the words from my short-term to my long-term memory. I am aware that much information that we learn is then lost; only about 50% of information is retained after one hour. I would therefore need to have a constant rotation of previously learned words, so that words were retained both over the course of one day, and then onwards over the course of many days and weeks. 

Oxbridge Interview Course & Question Bank

Private Oxbridge Interview Tuition

Articles & Resources

Shopping Cart
Scroll to Top

Intensive BMAT Course

BMAT Timetable

The BMAT Course