my fiend it is not is not possible this question has been asked for many time 
my friend it could be of 4 bloks==15+5+7+3=30....
1 5 1
but its right question comes in upsc 2013
The nswer of this question is tricky and the answer is 3!+1+13+7+3=30
2 3 2
plz explain mihir
did nt get this
3!=3*2*1=6 and factorial comes in 11sci maths
yes i know that thnks alott..