# Can you answer the hardest question from the GCSE maths exam?

Today was the GCSE maths exam today. If you’re not based in the UK, GCSEs are the exams taken by students aged 15-16. Only if you complete your GCSEs can you go on to A Levels. If you can’t get an A in GCSE maths, you will probably never be an investment banker.

The exam was allegedly difficult. And this was allegedly the hardest question. Can you answer it? Can you answer it in two minutes maximum? Answers, and workings, in the comments box at the bottom of the page please.

‘Tom travels from a to b and at a speed of 90km per hour. It takes him time ‘t’.  Alice travels from a to b at a speed of 70km per hour. It takes her time ‘t+ 1 hour’.

How long did it take for Tom to complete his journey?’

### Related articles:

The secret questions only the top 2% of mathematicians can answer

Seven of the hardest CFA exam questions and how to answer them

Five questions that will convert your banking interview into a job offer

1. t = 3.5 hours?

Am I right?

2. 90t=70(t+1)

20t=70

t=70/20=3.5 hours

Ivan

3. Tom total distance is 90t
Alice total distance is 70(t+1) = 70t +70
Thus 90t = 70t + 70, hence 20t = 70, thus t = 70/20 = 3.5hours

kazza

4. 90km/h -> complete AB in time t
=> at 10km/h -> complete AB in 9t (it would take 9 times as long)
=> at 70km/h -> complete AB in 9t/7 (it would be 7 times quicker than at 10km/h)

at 70km/h, completed in time t + 1. t + 1 = 9t/7

7t + 7 = 9t
2t = 7, t = 3.5 hours. Tom completes in 3.5 hours

DG

5. 4.5 hours

nikki

6. speed = distance / time

as both travel the same distance, each speed times its required time would be equal to others
90t = 70 (t+1)
90t = 70t + 70
t = 3.5
Tom takes 3.5 hours

Cecilia

7. 90t = 70(t+1)
t = 3.5

8======D

8. distance is same for both Tom and Alice, so u1t1=u2t2 , t2=t1+1 => u1t1-u2t1-u2=0 => t1(u1-u2)-u2=0 => t1=70/(90-70) => t1=3,5 hours

Mike

9. 90-70=20 km/h different between Tom’s and Alice’s speed
and we know that time is different 1 hour
70/20=3.5 Alice’s time
3.5-1=2.5 Tom’s time

anonymous

10. 2.5 h

Marina

11. 90-70=20 km/h different between Tom’s and Alice’s speed
and we know that time is different 1 hour
70/20=3.5 Alice’s time
3.5-1=2.5 Tom’s time

Marina

12. hi, I did the test today and I believe the answer is 4.5 hours as…..
90t-70t=20t
so 20t = the +1 on the 70 so,
20t=1hour
90/20=4.5hours
so tom takes 4.5 hours
(I think)

Ed

13. This was not the hardest on the paper, most people got this question as 3.5 hours, it was in the middle of the paper, the hardest was the question at the end, only a few answered both part (a) and part (b) correctly. You should have put that one up, unless you didn’t have access to the paper, and are in fact just using word of mouth, in which case, that’s not a basis to claim it is the hardest question on the paper, seeing as you are prevented from the use of diagrams.

WilliamStuart

14. And if I remember correctly it was only worth 2 or three marks out of the 70, so it wasn’t an important question, in terms of the whole paper.

WilliamStuart

15. If you are serious about this being the hardest question, it’s a disgrace to British math education. Seriously, this is a primary school level, what a waste of time “studying”. No wonder you can rarely find suitable locals to fill any analytic city positions.

AlexanderOrlov

16. I’m 16, having taken my GCSE maths exams a year early in June 2013 (achieving an A*) I can assure you that such a question is nowhere near the high end of the difficulty spectrum in GCSE maths exams.

AStudent

17. All these answers are wrong as they ignore time dilation.

pedanticone

18. MEOW 3.5 HOURS

TMT THE MONEY TEAM

sa

19. If this is the toughest Q then the maths std is very poor…

Mathswiz

20. average speed=total distance/total time hence average speedxtotal time=total distance
90t=70(t+1) as distance travelled is the same
90t=70t+70
20t=70
t=3.5h
QED.

JustMe

21. 4.5

123456ertyxcvbnm

22. 90t=70*(t+1)

solve T=3.5

yanfei mao

23. Distance = speed*time
So
90t = 70(t + 1)
90t = 70t + 70
20t = 70
t = 3.5

Tom took 3.5 hours.
This took 10 seconds.
I study in an Indian school, and this is the kind of calculation our 5th graders excel at.

Anna

24. No, it is not 3.5 hours. It is 3 minutes and 30 seconds

hilly

25. 90*t= 90t
t+1(70) = 70t+70
90t=70t+70
20t=70
t=3.5hours

Sid

26. just me is retarded

uk

27. Speed=Distance/Time

70km=90t/t+1
70(t+1)=90t
70t+70=90t
20t=70
t=7/2 or 3.5
Takes tom 3.5 hours to get from A to B

Kiran Singh

28. GCSE for 15-16 years old will get impossible at 2017 and onwards. It will be impossible to get even B forget A or A*. Government need to change this.

GCSE student

29. Another perhaps simpler way of doing so:
Write all distances out,the answer is when the same number matches an hour later as shown below. This is also good as it shows you the distance between A and B rather than just the time
1. 1.5. 2. 2.5. 3. 3.5. 4. 4.5
Tom. 90. 135 180 225 270 (315)350 395
Alice. 70 105 140. 175 210 245 280 (315)

MarcusAtkin

30. t=3.5 hrs. This comes no where near the hardest GCSE questions in England. And if you compare this level of ‘difficulty’ to the new 9-1 specification, this would be the easiest question on the exam paper.

Chloe

The comment is under moderation. It will appear shortly.

# React

Screen Name

Email

Consult our community guidelines here