APTITUDE

Numbers
H.C.F and L.C.M
Decimal Fractions
Simplification
Square and Cube roots
Average
Problems on Numbers
Problems on Ages
Surds and Indices
Percentage
Profit and Loss
Ratio And Proportions
Partnership
Chain Rule
Time and Work
Pipes and Cisterns
Time and Distance
Trains
Boats and Streams
Alligation or Mixture
Simple Interest
Compound Interest
Logorithms
Areas
Volume and Surface area
Races and Games of Skill
Calendar
Clocks
Stocks ans Shares
True Discount
Bankers Discount
Oddmanout and Series
Data Interpretation
probability
Permutations and Combinations
Puzzles
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Prime Numbers :-

A natural number larger than unity is a prime number if it
does not have other divisors except for itself and unity.
Note:-Unity i e,1 is not a prime number.
Properties Of Prime Numbers:-
->The lowest prime number is 2.
->2 is also the only even prime number.
->The lowest odd prime number is 3.
->The remainder when a prime number p>=5 s divided by 6 is 1 or 5.However,
if a number on being divided by 6 gives a remainder 1 or 5 need not be prime.
->The remainder of division of the square of a prime number p>=5 divide by 24 is 1.
->For prime numbers p>3, p²-1 is divided by 24.
->If a and b are any 2 odd primes then a²-b² is composite. Also a²+b²
is composite.
->The remainder of the division of the square of a prime number p>=5 divided
by 12 is 1.
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