how much time i have to give in all subject to get 90% percent marks in cbse class 12 (pcm)

@ ashok 
it varies from diffrent student to student . 
so, whatever time u are giving just utilise it to be the maximum . 
and getting 90 percent in cbse is easy that i experienced , just u need some rigrous practice . 
1- follow ncert as the first book , and these ncert will give u 80 percent marks . 
2-for maths go for exampler and r d sharma for integration part , ncert wl not help in integration part . 
3- solve at least last 5 years board paper , in chemi the ques are almost repeat everytime . 
4- for physics nothing is going to come outside ncert ( numericals ) }
and for derivation use arihhant allin one. 
5- at the prior days to exam ,go for sample paper solving , and not repeat your mistake . 
6- last but not the least – donot disturb your daily routine , just spent 2 -3 hrs per subject as self study , that is much enough for 90 percent . 
ALL THE BEST .

HEY 

FOLLOW THESE TIPS FOR SURE SUCCESS

 

Exam Preparation Tips

• Plan your studies well: Most students also prepare for medical entrance exams or engineering entrance exams along with Class XI and Class XII studies. They need to find topics that are common in their CBSE syllabus and entrance exam syllabus.When you study a topic that is common in both syllabuses, make sure you practice questions on it from Class 12th question papers as well as previous year papers of the entrance exam. 

• Tackle ‘difficult’ topics or subjects wisely: When you are feeling de-motivated, study easier topics. When your confidence level is high, study topics and subjects you find difficult and show them the power of your mind. Solve at least 5-10 numericals of Physics, Chemistry and Mathematics daily to gain speed.

• Important questions are in your Books: Most questions in CBSE boards are based directly on NCERT books. So, study them carefully.

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