Hi Suraj,
Yes, you can apply for Merchant Navy if you have aggregate 55% in PCM or B. Sc. , then you are required to have good marks in Physics and Chemistry.
Remember that you are required to do much of hard work to qualify this Merchant Navy Examination as you got less marks in Mathematics.
Feel free to ask doubts in the Comment Section.
You may refer to this article for more information about Merchant Navy.
I hope this information helps you.
Good Luck!
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