I have 20 days to revise class 11^th. syllabus as there is going to be a reshuffling test in my coaching institute. I am good in physics,have strong hold on some chapters of chemistry,and need lots of practice in maths.So what should be my strategy to score good marks in the test?

dear neelima 
if you are good in physics , then u must be good at maths , that two are corelated . 
so, what u can do , just take out the formula book for physics , read it ot once , and solve 2-3 mock test paper based on whole syllabus of physics . 
that u have to do in 6 days , rest u have 14 days . 
in this per week for chemi and maths . 
in chemi , specially inorganic part , u have to look over the reaction chart once again . and then for physical chemi ., practice ncert problem , and for organic , just revise the reaction inetrmediate part and nomenclature , rest u can do by yourself . 
and in maths 
1- make focus first on trigo , limit derivative and complex no , thses topics are imp . 
and for rest topics , only formula u required for solving the ques , 

u can even go through the revision note avaliable in our website . 

ALL THE BEST 
REGARDS