Operating Systems Interview Questions – Part I

Ankur Kulhari

Explain the main purpose of an operating system? Ans: Operating systems exist for: Easeness to use Efficient computational resource management Providing environment for the development and execution of programs. What is demand paging? Ans:Demand paging is a type of swapping in virtual memory management system in which pages of data are not copied from disk to RAM until they are …

Time and Work

Ankur Kulhari

The 1st and most important thing here to remember is that: Work is always considered as a unit, that means all the calculations will be done by assuming work as a unit entity. i.e. ‘Constructing a bridge’ work is considered as a unit task, Filling/emptying a tank or reservoir is considered as a unit entity. A man can wash 1 …

Simplification and Approximation

Ankur Kulhari

Simplification The most important thing to learn under simplification topic is the great BODMAS rule.The BODMAS RuleIt is important to follow the correct sequence of execution of operators in an expression. This means that to simplify an expression, the following order must be followed – B = Bracket, {the order – (), {} and [] – should be strictly followed} …

Time and Distance

Ankur Kulhari

Important Formulas: Speed = Distance / Time {To remember it, have you ever seen speedometer of any vehicle? In the speedometer “Kmph” is written in the center. That is the unit of speed. Kmph = Kilo meter per hour Kilo meter / hour Distance / Time Distance = Speed * Time If a vehicle covers certain distance d km with …

Pipe and Cistern

Ankur Kulhari

First let us understand frequently used and important keywords of this topic. Pipe: It is used to either fill the tank or empty the the tank. Tap: It is also user for, either to fill the tank or to empty the tank. Tank or Cistern or Reservoir: It is used to store the water. Inlet: A pipe or a tap …

What do you mean by programming language?

Ankur Kulhari

Programming Language is made up of words ‘programming’ and ‘language’. Therefore, first we need to understand word language. Language is an important mode of communication.As we all know that there are so many languages available in world and each language requires certain rules and regulations. Similarly ‘programming language’ is a subset of language which is used for communication with computing …

Percentage

Ankur Kulhari

Percentage is very important topic for aptitude subject. Direct questions are not asked from this topic but you will find use of this topic in almost all question of Data Interpretation (DI), Interest, Profit and Loss, Partnership etc. We will be discussing concept of percentage and shortcut tricks to solve these type of questions. Here is the table to convert …

Simple Interest

Ankur Kulhari

Interest: It is the extra money paid by the borrower to the owner (lender) as a form of compensation for the use of the money borrowed. Simple Interest (SI): SI = PRT/100 P=(100*SI)/RT R=(100*SI)/PT T=(100*SI)/PR Where, P= Principle or sum (It is the money borrowed or lent out for a time period T) R=Rate at which interest is charged on …

Compound Interest

Ankur Kulhari

Interest (I): It is the extra money paid by the borrower to the owner (lender) as a form of compensation for the use of the money borrowed Compound Interest (CI) CI = P(1+R/100)T – P A = P(1+R/100)T   Where, P= Principle or sum {It is the money borrowed or lent out for a time period T} R=Rate at which …