Quantitative Aptitude Shortcuts

Will you please provide the Tips and Tricks to Solve Quantitative Aptitude Test questions on Numbers?

[Raman Vij]

Here I am providing the Tips and Tricks to Solve Quantitative Aptitude Test questions on Numbers which you are looking for .

Quantitative Aptitude Shortcuts

Formulas of Number Series
1. 1 + 2 + 3 + 4 + 5 + … + n = n(n + 1)/2
2. (12 + 22 + 32 + ..... + n2) = n ( n + 1 ) (2n + 1) / 6
3. (13 + 23 + 33 + ..... + n3) = (n(n + 1)/ 2)2
4. Sum of first n odd numbers = n2
5. Sum of first n even numbers = n (n + 1)
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Mathematical Formulas
1. (a + b)(a - b) = (a2 - b2)
2. (a + b)2 = (a2 + b2 + 2ab)
3. (a - b)2 = (a2 + b2 - 2ab)
4. (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ca)
5. (a3 + b3) = (a + b)(a2 - ab + b2)
6. (a3 - b3) = (a - b)(a2 + ab + b2)
7. (a3 + b3 + c3 - 3abc) = (a + b + c)(a2 + b2 + c2 - ab - bc - ac)
8. When a + b + c = 0, then a3 + b3 + c3 = 3abc
9. (a + b)n = an + (nC1)an-1b + (nC2)an-2b2 + … + (nCn-1)abn-1 + bn
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Shortcuts for number divisibility check
1. A number is divisible by 2, if its unit's digit is any of 0, 2, 4, 6, 8.
2. A number is divisible by 3, if the sum of its digits is divisible by 3.
3. A number is divisible by 4, if the number formed by the last two digits is divisible by 4.
4. A number is divisible by 5, if its unit's digit is either 0 or 5.
5. A number is divisible by 6, if it is divisible by both 2 and 3.
6. A number is divisible by 8, if the number formed by the last three digits of the given number is divisible by 8.
7. A number is divisible by 9, if the sum of its digits is divisible by 9.
8. A number is divisible by 10, if it ends with 0.
9. 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.
10. A number is divisible by 12, if it is divisible by both 4 and 3.
11. A number is divisible by 14, if it is divisible by 2 as well as 7.
12. 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.

What are the Shortcuts for Maths formulas to solve the quantitative aptitude ?

[Kiran Chandar]

Ok, you want to know the Shortcuts for Maths formulas to solve the quantitative aptitude so here I am providing you.

Aptitude Formula shortcuts

Time And Distance -> Important Facts And Formulae

1. Speed = [Distance/Time],
Time=[Distance/Speed],
Distance = (Speed*Time)

2. x km/hr = [x*5/18] m/sec.

3. If the ratio of the speeds of A and B is a:b, then the ratio of the times taken by them to cover the same distance is 1/a : 1/b or b:a.

4. x m/sec = [x*18/5] km/hr.

5. Suppose a man covers a certain distance at x km/hr and an equal distance at y km/hr. then, the average speed during the whole journey is [2xy/x+y] km/hr.

Profit And Loss -> Important Facts And Formulae

Cost Price : The price at which an article is purchased, is called its cost price, abbreviated as C.P.

Selling Price : The price at which an article is purchased, is called its cost price, abbreviated as C.P.

Profit or Gain : The price at which an article is purchased, is called its cost price, abbreviated as C.P.

Loss : If S.Pis less than C.P., the seller is said to have incurred a loss.

1. Gain = (S.P.) - (C.P.)

2. Loss or gain is always reckoned on C.P.

3. gain% = [Gain*100/C.P.]

4. Loss = (C.P.) - (S.P.)

5. Loss% = [Loss*100/C.P.]

6. S.P. = (100+Gain%)/100 * C.P.

7. S.P. = (100-Loss%)/100 * C.P.

8. C.P. = 100/(100+Gain%) * S.P.

9. C.P. = 100/(100-Loss%) * S.P.

10. If an article is sold at a gain of say, 35%, then S.P. = 135% of C.P

11. If an article is sold at a loss of say, 35%, then S.P. = 65% of C.P.

Volume And Surface Area -> Important Facts And Formulae

I. Cubiod
Let length = l, breadth = b and height = h units. Then,

1. Volume = (l x b x h) cubic units.
2. Surface area = 2 (lb + bh + lh)

II. Cube
Let each edge of a cube be of length a. Then,

1. Volume = a³ cubic units.
2. Surface area = 6a² sq. units.
3. Diagonal = √3 a units.

III. Cylinder
Let radius of base = r and Height (or length) = h Then,

1. Volume = (∏r²h) cubic units.
2. Curved surface area = (2∏rh) sq. units.`23








For more formulas here I am attaching a pdf file, it is free to download.

I am preparing for the government exam and I want to crack them, please share some short cuts to solve Quantitative Aptitude questions so I can speedily solve the questions?

[Arun Vats]

As per your request, I am going to explain you some short cut tips for the quantitative aptitude with examples.

Subtraction Of Numbers Close To Multiple Of 10

56 – 48
56 – (50 – 2)
= 56 – 50 + 2
= 6 +2
= 8

General Shortcut Method For Finding Squares

Step 1: Find Square of B
Step 2: Find 2×A×B
Step 3: Find Square of A

Problem Based on Age:

Example 1: The ratio of present age of A & B is 2 : 3 the present age of A is 30 years. Find the age of B after 5 years ?
Answer :

Step 1: A : B present age ratio is 2 : 3 and A = 30 years.
Step 2: B present age is 30 / 2 x 3 = 45 years.
Step 3 : B age after 5 years is 45 + 5 = 50 years.

Example 2 : Niloy is as younger to Ganesh as he is older to Dev. If the sum of the ages of Ganesh & Dev is 58 years. What is Niloy age ?
Answer :

Step 1 : G – N = N – D
Step 2 : G + D = 2N
Step 3 : 58 = 2N
Step 4 : N = 29 years

Time and work

Time taken single piece of work, If A Person do a piece of work or job in n days, then person’s finish the work in n days = 1 / n.
A person do a piece of work in 1 days = 1 / n, then person can finish the work in n days.
If A person twice work a workman as B person, then Ratio of work done by A and B is = 2 : 1.
The reciprocal of day”s work gives the alone time i.e., alone time ( or time to complete a job by a single person) = 1 / 1 day”s work
when more then one person working on tha same type of work, then there combined work = sum of 1 day”s work by each person. suppose P, Q , R work same piece of work by each person (P + Q + R)”s 1 day’s work = P’s day’s work + Q’s day’s work + R’s day’s work.