Aptitude

1. PRESENTED BY
LBS MCA CRASH
COURSE
SUBJECT : Quantitative Aptitude and Logical Ability

2. AVERAGE
Average =
Average of first n natural numbers = (n+1)/2
Average of first n even numbers = n+1
Average of first n odd numbers = n
Sum of Observations
Total Number of
Observations

3. 1. The average age of A, B, C is 28 years. If the average age of B and C is
29 years, what is the age of A in years?

4. 2. The average of 10 numbers is 23. If each number is increased by 4,
what will the new average be?

5. 3. The average of 7 consecutive numbers is 20. What is the largest of
these numbers?

6. 3. The average age of a family of four is 30 years. If the father is 40 years
old, what is the average age of the remaining three family members?
a) 25
b) 30
c) 35
d) 40

7. Coding and Decoding
LETTER CODING
1.In a certain language, if PRICE is coded as SVNIL then how will COST be
coded:
a) FSXY
b) FSWY
c) FTWZ
d) FSXZ

8. 2. In a certain language, if BRING is coded as GNIRB then how will LONG
be coded :
a) NGOL
b) GNOL
c) GROB
d) GNOL

9. 3. In a certain language, if COME is coded as BDNPLNDF then how will
POST be coded :

10. 4. If HOME is written as PIFN is it a certain code? How is NICE written in
that code?
a) JOMD
b) DFOJ
c) JMFD
d) JOFD

11. 4. If CERTAIN is written as XYPIRTE is it a certain code? How is RAIN
written in that code?

12. NUMBER CODING
In a certain code, AGE is written as 175, how is CAR written in that code?
We used the number of alphabets here.
A = 1
G = 7
E = 5
For CAR
C = 3
A= 1
R = 18 = 1+8 = 9
Hence, CAR is written as 319.

13. 7. If C O V E R is coded as 63, then BASIS will be coded as?
a) 49 b) 50 c) 54 d) 55
C O V E R is coded as 3 + 15 + 22 + 5 + 18 = 63. [C + O + V + E + R]
Now, in B A S I S,
B = 2, A = 1, S = 19, and I = 9.
Thus, B A S I S will be coded as 2 + 1 + 19 + 9 + 19 = 50.
Hence, the answer is b).

15. 8. If ‘WORK’ is coded as 4 12 9 16 , then ‘WOMEN’ will be coded as:
a) 4 12 14 26 13
b) 4 26 14 13 12
c) 23 12 26 14 13
d) None of the above
(The logic followed here is, ⇒
Opposite positional value of the letters)

16. Seating Arrangement
3 STEPS :
i. Count total number of people.
ii. Draw a "Seating Frame".
iii. Solve individual statements that are completely certain,
then merge all the solved sets into a final complete set.
THREE TYPES :
1.Linear Arrangement
2.Circular Arrangement
3.Square/Rectangle Arrangement

17. Practice Questions :
1. A, P, R, X, S and Z are sitting in a row. S and Z are in the centre. A and P
are at the ends. R is sitting to the left of A. Who is to the right of P ?
Total no. of people = 6
S/Z
S/Z
A/P A/P
A
P S/Z S/Z R

18. 2. A, B and C are three boys while R, S and T are three girls. They are sitting
such that the boys are facing the girls. A and R are diagonally opposite to
each other. C is not sitting at any of the ends. T is left to R but opposite to
C.
(A). Who is sitting opposite to B ?
(B). Who is sitting diagonally opposite to B ?
3 boys
3 girls

19. 3. K, L, M, N, O, P and Q are sitting in a circle facing at the centre and playing
cards.
a) O is neighbour of K and N.
b) Q is not between P and M.
c) P is to the immediate right of K.
d) L is second to the left of Q.
Total = 7

20. 4. Which of the following does not have the pair of persons sitting adjacent to
each other?
a) LK
b) ML
c) NO
d) QN

21. 5. What is the position of P?
a) Second to the right of M
b) To the immediate left of K
c) Second to the left of M
d) To the immediate right of L

22. 6. In a class of 90, where girls are twice that of boys, Satheesh is ranked
14th from the top. If there are 10 girls ahead of Satheesh, how many
boys are after him in rank?
a)23 b)26 c)25 d)22
Total students = 90
boys, girls
30 boys, 60 girls
Rank
Sadeesh

23. 7. Among 5 persons P,Q,R,S and T each having different amount of
money, R has more money than only T. Q has more money than S but less
than P. Who among them has the highest amount of money ?
a)Q
b)T
c)P
d)Data Inadequate
money