I have brought Pearson 's Crack IIM Indore IPM entrance exam. Will this be sufficient or should I buy 1st edition as well? Any other book suggestions?

According to one of my friends, who is an alumnus of IIM Indore, books like Pearson’s are not sufficiently good for preparation. Most of them are outdated and follow the old syllabus and the question type that was asked previously during the exams. If you want to crack the entrance exams for IPM, then you need to be consistent while preparing for the exam and thorough with all the concepts. 

You can refer to the basic NCERT books along with Wren and Martin's latest edition for the same. These books can help you immensely to improve your vocabulary.

Be consistent with your preparation, and you should be through.