Interview Question for Senior Consultant at IBM:

As mentioned previously, don't make the mistake of working this out mathematically. You are required to guess. Random numbers to make up:

i) Annual motor license tax;
ii) Number of cars on the road;
iii) Fuel used by cars per year on average;
iv) Price of fuel per litre;
v) etc.

Note, as I've put it down is already incorrect. These are variables, not numbers. If you worked from these variables you may be tempted into creating an equation before guessing your numbers. This is not necessary.

The range of answers they will accept varies between 5 to 20%. I.e. useless.