Hello everyone.

This is not really a homework but it is very urgent.

I have a Discrete math exam in one day and this problem is giving me so much headache!

$\displaystyle x\equiv 1(\bmod 4)$ (1)

$\displaystyle x\equiv 2(\bmod 5)$ (2)

$\displaystyle x\equiv 3(\bmod 7)$ (3)

I tried finding inverses as well as reducing these three equations to two equations like:

$\displaystyle x+3\equiv 0(\bmod 28)$

$\displaystyle x+3\equiv 0(\bmod 5)$

and in both cases the result does not work out for the equation (3).

Could anyone please explain me why it is so and how to do this in a right way?