PROFIT AND LOSS

Quantitative Aptitude Study Notes 
 Bank & SSC
Exam

PROFIT AND LOSS
You know that quantitative
aptitude section is most important in bank
exams in PO and
Clerk and for
other competitive exams because if you want good score in bank exam then you
have to score good in maths. In competitive exams the most important thing is
time management, if you know how to manage your time then you can do well in Bank Exams. That’s where maths shortcut
tricks and formula are comes into action. So continuously we are providing
shortcut tricks on different maths topics.
The one of the most important topic
in maths is PROFIT AND LOSS. You
should know how to calculate profit and loss in very short time. For this here
we are providing shortcut tricks and quicker
method
to calculate profit and loss
in maths.

PROFIT AND LOSS
For profit and loss we use rule of fraction is dominant. We should
understand this rule very well because it is going to be used in almost all the
questions.
If our required value is greater
than the supplied value, we should multiply the supplied value with a fraction
which is more than one. And if our required value is less than the supplied
value, we should multiply the supplied value with a fraction which is less than
one.
If there is a gain of x%, the
calculating figures would be 100 and (100 + x).
If there is a loss of y%, the
calculating figures would be 100 and (100 – y).
If the required value is more
than the supplied value, our multiplying fractions should be 100 + x / 100
Or
100 / 100 – y
(both are greater than 1).
If the required value is less than
the supplied value, our multiplying fractions should be
Fractions should be 100 / 100 + x
Or
100 – y / 100
(Both are less than 1).
PROFIT =
SELLING PRICE (SP) – COST PRICE (CP)
LOSS = COST
PRICE (CP) – SELLING PRICE (SP)
To find the gain or loss per cent
%
The profit or loss is generally
reckoned as so much per cent on the cost.
GAIN OR LOSS
PER CENT % = loss or gain × 100 / CP
CASE
1:
SIMPLE BASIC QUESTIONS FOR PROFIT
AND LOSS:
Example 1: A woman buys a toy for 25 Rs and
sells it for 30 Rs. Find her gain per cent?
Solution: Gain % = gain × 100 / CP
= 5 × 100 / 25
= 20%
Example 2: A girl buys a pen for 25 Rs and
sells it for 20 Rs. Find her loss per cent?
Solution: Loss % = loss × 100 / CP
= 5 × 100 / 25
= 20%
Example 3: If a man purchases 11 oranges
for 10 Rs and sells 10 oranges for 11 Rs. How much profit or loss does he make?
Solution:
Suppose that the person bought 11
× 10 = 110 oranges.
CP of 110 oranges = 10 × 110 / 11
= 100 Rs.
SP of 110 oranges = 11 × 100 / 10
= 121 Rs.

Profit = 121 Rs – 100 Rs = 21 Rs
And % profit = profit × 100 / CP
= 21 × 100 / 100
=21%
We can also
use shortcut method or quicker method for this type of questions:
Quicker
method:
rewrite the
statements as follows:
Purchase                    11 oranges for 10 Rs.
Sell                              10 oranges for 11 Rs.
Now, percentage profit and loss
is given by:
11 * 11 – 10 * 10  × 100      
       10 * 10
= 21%
Since the sign is +ve, there is a
gain of 21%.
The above form of structural
adjustment should be remembered. The first line deals with purchase whereas the
second line deals with sales. Once you get familiar with the form, you need to
write only the figures and not the letters.
Example 4: A man purchases 8 pens for 9 Rs
and sells 9 pens for rupees 8. How much profit or loss does he make?
Solution: we will solve this questions
quicker trick:
Purchases                  8 pens for 9 Rs
Sells                            9 pens for 8 Rs
% profit or loss = 8 × 8 – 9 × 9       ×
100
                                    9
× 9
= -1700/81
= -20.98%
Since the sign is –ve, there is a
loss of 20.98%.
CASE
2:
Example 5: A dishonest dealer professes to
sell his goods at cost price, but he uses a weight of 960 gm for the kg weight.
Find his gain per cent.
Solution: suppose goods cost the
dealer Re 1 per kg. He sells for Re 1 what cost him Re 0.96.
Gain on Re 0.96 = Re 1 – Re 0.96
= Re 0.04
Gain on Rs 100 = 0.04 × 100 /
0.96
= Rs 25 / 6
Gain % = 25/6%
We can also solve this question
by using direct formula, it will save your time in the exam.
Direct
formula:
% Gain  =                  ERROR                       × 100
                
       True value – Error
Or
% Gain
=  true weight – false weight     × 100
                        False
weight
= 40 × 100 / 1000 – 40
=25/6%
CASE
3:
In the profit and loss topic the
next example on;
TO FIND THE
SELLING PRICE:
Example 6: A man bought a cycle for Rs 250.
For how much should he sell it so as to gain 10%?
Solution:
If CP is Rs 100, the SP is Rs
110.
If CP is Rs 1, the SP is Rs 110 /
100.
If CP is Rs 250, the SP is Rs
110×250 / 100
= Rs 275.
Another suggested method (by rule
of fraction)
If he wanted to sell the bicycle
at a gain of 10%, the selling price (required value) must be greater than the
cost price (supplied value), so we should multiply Rs 250 with a more than one
value fraction. Since there is a gain, our calculating figures should be 100
and (100+10) and the fraction should be 110/100.
Thus, selling price = 250 ×
110/100
= Rs 275.
CASE
4:
TO FIND THE
COST PRICE:
Example 7: By selling goods for Rs 352.88, I lost 12%. Find
the cost price?
Solution: CP should be more than SP; so we
multiply SP by
100 / 100 – 12 = 100 / 88
(a fraction which is more than
one)