Symbols and Notations : Logical Reasoning

  • Instructions (1-2) :-
    Thease questions are based on the following information.
    ( I ) 'A * B' means 'A is brother of B'
    ( II ) 'A / B' means 'B is mother of A'
    ( III ) 'A – B' means 'A is father of B'
    ( IV ) 'A + B' means 'B is sister of A'
  • 1. Which of the following means L is daughter of H?
A.) L + K / J – H
B.) H – J * R + L
C.) L – J * H / K
D.) L + W * R / H

Answer: Option 'B'

H – J * R + L 
L -> Sister R ,
R -> Brother J,
J -> Fother H 
Therefore, L is daughter of H.

  • 2. How is S related to T in the Expression: T / P + S ?
A.) Daughter
B.) Sister
C.) Niece
D.) Aunt

Answer: Option 'D'

T / P + S 
S -> Sister P ,
P -> Mother T 
Therefore, P is the mother of T and S is the sister of P. 
Then S is Aunt of T.

  • Instructions (3 - 4) :-
    Thease questions are based on the following information.
    ( I ) 'A * B' means 'A is father of B'
    ( II ) 'A – B' means 'A is sister of B'
    ( III ) 'A + B' means 'A is mother of B'
    ( IV ) 'A/B' means 'A is sister of B'
  • 3. In the expression D + F * O / P, how is O related to D?
A.) Grand daughter
B.) Son
C.) Grand son
D.) Daughter

Answer: Option 'C'

D + F * O / P 
D + F means D is mother of F 
F * O means F is father of O 
O * P means O is brother of P 

  • 4. Which of the following represents ‘ J is son of F ‘’ ?
A.) J / R – T * F
B.) J + R – T * F
C.) J / M – N * F
D.) None of these

Answer: Option 'D'

A.) J / R – T * F 
J + R means J is brother of R 
R - T means R is sister of T 
T * F means T is fother of F 
Therefore, J is Uncle of F 
B.) J + R means J is Mother of R 
J is a female. 
C.) J / M means J is brother of M 
M – N means M is sister of N 
N * F means N is father of F 
Therefore J is uncle of F.

  • Instructions : (5 - 7) -
    In the following questions, the Symbols @, ©, $ , % and & are used with the following meanings as illustrated below.
    ‘A $ B’ means ‘A is not greater than B’.
    'A @ B' means 'A is neither smaller then nor equal to B'.
    'A & B' means 'A is neither greater than nor equal to B'.
    'A © B' means 'A is neither greater than nor smaller than B'.
    'A % B' means 'A is not smaller than B’.
    In each of the following question assuming the given statements to be true, find out which of the two conclusions I and I I given below these are definitily true.
  • 5. Statements: 
    C & D, D $ E, E © F 
    Conclusions: 
    I .F @ C 
    II. E @ C
A.) If only conclusion I is true
B.) If only conclusion II is true
C.) If either conclusion I or conclusion II is true
D.) If both conclusions I and II are true.

Answer: Option 'D'

‘A $ B’ -> A !> B, therefore A = B. 
‘A @ B’ -> A B. 
‘A & B’ -> A !> B and A ‘A © B’ -> A !> B and A ‘A % B’ -> A C & D -> C < D 
D $ E -> D = E 
E © F -> E = F 
Therefore C < D = E = F 
Conclusions: 
1. F @ C -> F > C ( True ) 
2. E @ C -> E > C ( True )