MAH MCA CET flashcards

31 cards. Read the term and the definition here. The deck at the top of this page is optional.

Simple interest formula

SI equals principal multiplied by rate multiplied by time, divided by 100. Interest is computed only on the original principal, so each year adds the same amount.

Compound interest formula

Amount equals principal times (1 + R/100) raised to the power T. Interest is added to the principal each period, so the base grows every year.

Train crossing a platform

Time taken equals the sum of train length and platform length divided by train speed. Crossing a pole or a person uses only the train's own length.

Work done together

If A finishes in a days and B in b days, together they finish in ab/(a + b) days. Their combined one-day rate is 1/a plus 1/b.

nCr and nPr

nPr equals n factorial divided by (n − r) factorial, used when order matters. nCr equals nPr divided by r factorial, used when order does not matter.

Sum of first n numbers

The sum of the first n natural numbers is n(n + 1)/2. The sum of their squares is n(n + 1)(2n + 1)/6, and of cubes is the square of the first sum.

Addition rule of probability

For two events, P(A or B) equals P(A) plus P(B) minus P(A and B). The subtraction avoids double-counting outcomes shared by both events.

Boat and stream speeds

Downstream speed is boat plus stream, upstream is boat minus stream. Boat speed in still water is the average of the two; stream speed is half their difference.

Opposite letter positions

Letters are numbered A = 1 through Z = 26. The opposite of position p sits at 27 − p, so A pairs with Z, B with Y, and M with N.

Clock hand angle

The angle between hour and minute hands is the absolute value of 30H − 5.5M degrees. If it exceeds 180, subtract from 360 for the smaller angle.

Leap year weekday shift

An ordinary year shifts the weekday of a given date by one day, while a leap year shifts it by two because of the extra 29 February day.

Valid syllogism conclusion

A conclusion is valid only if it holds in every possible diagram satisfying the premises. A possibility in one arrangement is not enough to accept it.

Direction sense displacement

Track north–south and east–west movement as separate signed totals. The straight-line distance from start is the square root of the sum of squares.

Blood relation tree method

Draw generations as vertical levels and mark siblings horizontally. Apply each stated relation from the viewpoint of the person named in the question.

Number series strategy

First test constant differences, then constant ratios. If neither fits, split into odd-position and even-position terms and look for separate rules in each.

Coding decoding shift check

Align each plain letter with its coded letter and count the position gap. A constant gap means a shift cipher; a reversed alphabet means mirror coding.

Seating arrangement facing rule

For people facing north, left means west and right means east. For those facing south the directions swap, so fix orientation before placing anyone.

Subject verb agreement rule

A singular subject takes a singular verb and a plural subject a plural verb. With either–or and neither–nor, the verb agrees with the nearer subject.

Present perfect tense use

Formed with has or have plus the past participle, it describes a past action linked to the present, often with since, for, already, or yet.

Active to passive conversion

The object becomes the subject, the verb becomes a form of be plus the past participle, and the original subject follows by, keeping the same tense.

Prepositions of time

Use in for months, years, and long periods; on for days and dates; at for clock times and fixed points such as at noon.

Affect versus effect

Affect is normally a verb meaning to influence. Effect is normally a noun meaning a result, as in the effect of the policy.

Direct to indirect speech

Present tenses shift to past, today becomes that day, and tomorrow becomes the next day. Pronouns change to reflect the reporter's viewpoint.

Idiom bite the bullet

This idiom means to face a difficult or unpleasant situation with courage and endure it, rather than to avoid or postpone the problem.

Computer generations

First generation used vacuum tubes, second transistors, third integrated circuits, fourth microprocessors, and fifth artificial intelligence with parallel processing.

RAM versus ROM

RAM is volatile working memory that loses contents when power is cut. ROM is non-volatile and holds permanent firmware such as the boot instructions.

Memory unit conversions

One byte equals eight bits. One kilobyte is 1024 bytes, one megabyte is 1024 kilobytes, and one gigabyte is 1024 megabytes.

Compiler versus interpreter

A compiler translates the entire source program into machine code before running it. An interpreter translates and executes one statement at a time.

OSI model layer count

The OSI reference model has seven layers, from physical and data link up through network, transport, session, presentation, and application.

Common port numbers

HTTP uses port 80, HTTPS uses 443, FTP uses 21, and SMTP uses 25. These standard ports identify the service a server offers.

Primary versus foreign key

A primary key uniquely identifies each row in a table. A foreign key is a column that references the primary key of another table to link records.