Government & Defence Entrance Exam

Yes, of course you can get job in ISRO after completing M.Sc in Mathematics. You can apply for the posts like, Scientist/Engineer posts.
Eligibility Criteria:
Qualification :
The applicant must quality in M.Sc Degree should be in first Class with an aggregate minimum of 65% (Average of all semesters) or CGPA/CPI grading of 6.5 on a 10 scale or equivalent from a recognized university.
Age Limit:
The applicant age should be below 35 years (40 years in case of SC/ST candidates and 38 years for OBC candidates.) Ex-Serviceman and Persons with Disabilities are eligible for age relaxation as per Govt. of India orders). For PWD persons, orders on reservation to the extent applicable will be extended for the above posts.
For more more Information please visit here - www.isro.gov.in

Sub Inspector in Delhi Police is now recruited by Staff Selection Commission (SSC) through graduate level examination under central armed police forces (CAPF) which covers all the para military forces of country. As lots of people aspire to get into Delhi Police (as life is relatively easy as compared to para military forces) and other perks the cut off is really high.
There are two examinations on same day one is Prelims and the other is mains but mains is only counted if you clear prelims, physical and medical test.
A prelim consists of four sections Quantitative Aptitude, Logical Reasoning, English and General Studies. All sections are of 50 marks just like any other SSC graduate level exam. The only different thing is the main exam consists of ONLY ENGLISH. Yes, all the Sub-Inspectors in forces have to pass ENGLISH examination.
After clearing the prelims then you are called for Physical & Medical test where there are 5 activities which have to be cleared. Mind you, you have to clear all the five activities. Firstly you have to clear for 1600m in 6mins 30sec. half of the crowd is not able to clear it and they are rejected. Second is 100 meters in 14 sec. then long jump for 15 feet, high jump for 3.50 feet and short put. If you clear all the activities then you have to come next day for medical. They check each and every body part in the medical.

There is only one paper for constable post which is general paper. General paper consist of sections like general knowledge, general awareness, mathematics, general science. General knowledge includes history, geography, social science, economy, polity. Difficulty level of questions is moderate. we recommend some good books which are given below.
MP Police constable Exam book by Career Disha publication is one of the best book for this exam. It covers whole syllabus of general paper and also includes objective questions for practice.
MP Police Constable Recruitment Exam Guide is also good book. You can refer one of these books. Also read daily newspaper and note down important news which is important for current affairs.