I'm sorry but your answer is wrong. Everybody knows that Micro-Machines come in collections of five, therefore if John and Jenny have a combined total of three Micro-Machines you must have the remaining two.
Unfortunately due to a legal loophole I have discovered that I am not authorized to banish you to illogical space, hopefully this loophole will have been closed by the time you solve the next question.

That was a silly mistake, I will think more logically in future
I was lucky this time but I'm not taking any chances, I wish to end my quest now