Company: Accenture services

Quantitative Aptitude Formula Handbook

I. Arithmetic Progression.

Definition: If each term of a series differs from its preceding term by a constant, then such
a progression is called arithmetic progression.
e.g: 2,5,8,11
In the above sequence the difference between any two terms in 3.
Formula:
Consider an AP : a, (a + d), (a + 2d), (a + 3d),(a + 4d),….
1) n th term of the above sequence = Tn = a + (n – 1)d
2) Sum to n no of terms Sn = n / 2 (2a + (n – 1)d)
3) Another formula for Sn = n / 2 (first term + last term)

II. Geometric Progression.

Definition: Any progression or sequence with successive terms having a common ration is
called geometric progression.
e.g: 2,4,8,16…
In the above sequence the common ratio is 2 for any two successive terms
Formula:
Consider a GP – a, ar, ar2…. where a is the first term and r is the common ratio
4) n th term, Tn = arn-1
5) Sum to n terms, Sn = a(1 – rn)/(1-r)
6) In case r lies between -1 and +1 then Sum of all terms of the series = a/ (1 – r)

III. HCF and LCM

7) Product of two numbers = Their HCF X Their LCM

IV. Percentages

8) How to express a/b as percentage?
Ans: (a/b) x 100
9) How to express a percentage of b?
Ans: (a/100) x b
10) If the price of an item increases by A%, then the reduction in consumption so as
not to increase the expenditure is
Ans: A / (100 + A) x 100 %
11) If the price of an item decreases by A%, then the increase in consumption so as not
to decrease the expenditure is:
Ans: A / (100 – A) x 100 %

V. Profit And Loss

12) Profit = Selling Price – Cost Price
13) Loss = Cost Price – Selling Price
14) Profit Percentage = (Profit / Cost Price) x100
15) Loss Percentage = (Loss / Cost Price) x100

VI. Time And Work

16) N1 x R1 = N2 x R2 = W
Here: N = number of working men; R = rate of work done per man; D = days; W =
total work done.

VII. Boats And Streams

Let b = boat speed, s = stream speed, d = distance and t = time
17) Smooth water equation
b = d / t
18) Upstream equation
b + s = d/t
19) Downstream speed.
b – s = d/t

VIII. Simple and Compound Interest

20) For Interest Compounded Annually
Total Amount = P (1+(R/100))n
21) For Interest Compounded Half Yearly
Total Amount = P(1+(R/200))2n

22) For Interest Compounded Quarterly
Total Amount = P(1+(R/400))4n
23) Simple Interest = (Principal X Rate X Time) / 100
SI = PRT/100
Where P = capital amount, R = annual rate, T = time period in years