Tricks to solve the aptitude questions - 2017-2018 StudyChaCha

#1
May 6th, 2014, 01:01 PM
 Unregistered Guest Posts: n/a
Tricks to solve the aptitude questions

Will you please give me some good Tricks to solve the aptitude questions…………….???
#2
May 7th, 2014, 12:17 PM
 Super Moderator Join Date: Dec 2011 Posts: 21,910
Re: Tricks to solve the aptitude questions

Solving the aptitude test questions with accuracy as well as quickly is asked in most of the competitive entrance examination. For this should practice again and again, as practice makes a man perfect.

Following are some Short tricks to solve aptitude questions:

Formulas of Number Series
1 + 2 + 3 + 4 + 5 + … + n = n(n + 1)/2
(13 + 23 + 33 + ..... + n3) = (n(n + 1)/ 2)2
(12 + 22 + 32 + ..... + n2) = n ( n + 1 ) (2n + 1) / 6
Sum of first n odd numbers = n2
Sum of first n even numbers = n (n + 1)

Mathematical Formulas
(a + b)(a - b) = (a2 - b2)
(a + b)2 = (a2 + b2 + 2ab)
(a3 - b3) = (a - b)(a2 + ab + b2)
(a3 + b3 + c3 - 3abc) = (a + b + c)(a2 + b2 + c2 - ab - bc - ac)
When a + b + c = 0, then a3 + b3 + c3 = 3abc
(a + b)n = an + (nC1)an-1b + (nC2)an-2b2 + … + (nCn-1)abn-1 + bn
(a - b)2 = (a2 + b2 - 2ab)
(a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ca)
(a3 + b3) = (a + b)(a2 - ab + b2)

Shortcuts for number divisibility check

A number is divisible by 5, if its unit's digit is either 0 or 5.

A number is divisible by 6, if it is divisible by both 2 and 3.

A number is divisible by 12, if it is divisible by both 4 and 3.

A number is divisible by 14, if it is divisible by 2 as well as 7.

Two numbers are said to be co-primes if their H.C.F. is 1. To find if a number, say y is divisible by x, find m and n such that m n = x and m and n are co-prime numbers. If y is divisible by both m and n then it is divisible by x.

A number is divisible by 2, if its unit's digit is any of 0, 2, 4, 6, 8.

A number is divisible by 3, if the sum of its digits is divisible by 3.

A number is divisible by 4, if the number formed by the last two digits is divisible by 4.

A number is divisible by 8, if the number formed by the last three digits of the given number is divisible by 8.

A number is divisible by 9, if the sum of its digits is divisible by 9.

A number is divisible by 10, if it ends with 0.

A number is divisible by 11, if the difference of the sum of its digits at odd places and the sum of its digits at even places, is either 0 or a number divisible by 11.

To crack the examination you should learn the Basics and Remember the Basic formula and Note down in a Book for future reference. You should have an idea on the number and type of questions asked for the test.
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