Data Sufficiency


  1. Salary of A and B is in ration 3:4 and expenditure is in ratio 4:5. What is the ratio of their saving?
    I. B's saving is 25% of his salary.
    II. B's salary is ₹ 2500.









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    Given that their salaries are in the ratio of 3:4 and expenditure is in the ratio of 4:5 hence we can assume that salary of A and B are 3x and 4x and their expenditures are 4y and 5y.
    Now we need to find the ratio of (3x - 4y)/(4x - 5y)
    Consider statement I alone:
    Giving of B is 25% of his salary hence his expenditure must be 75% so 3/4(4x) = 5y or 3x = 5y from this we can find the required ratio hence this statement is sufficient.
    Consider statement II alone :
    Given that 4x = 2000 or x = 500 but from this we can not find the value of y and hence we can not find the ratio of their savings.

    Correct Option: A

    Given that their salaries are in the ratio of 3:4 and expenditure is in the ratio of 4:5 hence we can assume that salary of A and B are 3x and 4x and their expenditures are 4y and 5y.
    Now we need to find the ratio of (3x - 4y)/(4x - 5y)
    Consider statement I alone:
    Giving of B is 25% of his salary hence his expenditure must be 75% so 3/4(4x) = 5y or 3x = 5y from this we can find the required ratio hence this statement is sufficient.
    Consider statement II alone :
    Given that 4x = 2000 or x = 500 but from this we can not find the value of y and hence we can not find the ratio of their savings.


  1. What is the average height of the class?
    I. Average height of the class decreases by 1 cm i we exclude the tallest person of class whose height is 56 cm.
    II. Average height of the class increase by 1 cm if we exclude the shortest person o the class whose height is 42 cm.









  1. View Hint View Answer Discuss in Forum

    Let x be the average height of the class and n be the number of students in the class.
    Consider statements I alone
    xn - 56 = (x - 1)(n -1)
    ⇒ x + n = 57 .............(i)
    Hence, the value of x cannot be found. So, I alone is not sufficient.
    Consider statement II alone:
    xn - 42 = (x + 1)(n - 1)
    ⇒ x - n = 41 .............(ii)
    Hence, the value of x cannot be found. So, II alone is not sufficient.
    Both the statements together are sufficient as the value of x can be found by solving (i) and (ii)

    Correct Option: C

    Let x be the average height of the class and n be the number of students in the class.
    Consider statements I alone
    xn - 56 = (x + 1)(x -1)
    ⇒ x + n = 57 .............(i)
    Hence, the value of x cannot be found. So, I alone is not sufficient.
    Consider statement I alone:
    xn - 42 = (x + 1)(n - 1)
    ⇒ x - n = 41 .............(ii)
    Hence, the value of x cannot be found. So, II alone is not sufficient.
    Both the statements together are suficient as the value of x can be found by solving (i) and (ii)



  1. Ram is taller than Shyam and Jay is shorter than Vikram. Who is the shortest among them?
    I. Ram is the tallest.
    II. Shyam is taller than Vikram.









  1. View Hint View Answer Discuss in Forum

    Given that Ram > Shyam, Vikram > Jay.
    Hence from this we can conclude that neither Ram nor Vikram is the shortest. And we have to find the shortest. And we have to find the shortest among them:
    Consider statement alone:
    We know that that Ram is not the shortest, either Shyam or Jay is the shortest.
    Hence (I) alone is not sufficient.
    Consider statement I alone Shyam > Vikram.
    From the given information and the information in (II), we get Ram > Shyam > Vikram > Jay.
    Hence, (II) alone is sufficient.

    Correct Option: B

    Given that Ram > Shyam, Vikram > Jay.
    Hence from this we can conclude that neither Ram nor Vikram is the shortest. And we have to find the shortest. And we have to find the shortest among them:
    Consider statement alone:
    We know that that Ram is not the shortest, either Shyam or Jay is the shortest.
    Hence (I) alone is not sufficient.
    Consider statement I alone Shyam > Vikram.
    From the given information and the information in (II), we get Ram > Shyam > Vikram > Jay.
    Hence, (II) alone is sufficient.


Direction: are followed by two statements labelled as I and II. Decide if these statements are sufficient to conclusively answer the question. Choose the appropriate answer from the options given below:

  1. Given below is an equation where the letters represent digits. (PQ) . (RQ) = XXX. Determine the sum of P + Q + R + X.
    I. X = 9.
    II. The digits are unique. [3]











  1. View Hint View Answer Discuss in Forum

    Given relationship is (PQ)(RQ) = XXX
    Since X can take 9 values from 1 to 9 hence we have 9 possibilities
    111 = 3 x 37 444 = 12 x 37 777 = 21 x 37
    222 = 6 x 37 555 = 15 x 37 888 = 24 x 37
    333 = 9 x 37 666 = 18 x 18 999 = 27 x 37
    But out of these 9 cases only in 999, we get the unit's digit of two numbers the same. Since it is a unique value, hence we need neither statement I nor statement II to answer the question.

    Correct Option: E

    Given relationship is (PQ)(RQ) = XXX
    Since X can take 9 values from 1 to 9 hence we have 9 possibilities
    111 = 3 x 37 444 = 12 x 37 777 = 21 x 37
    222 = 6 x 37 555 = 15 x 37 888 = 24 x 37
    333 = 9 x 37 666 = 18 x 18 999 = 27 x 37
    But out of these 9 cases only in 999, we get the unit's digit of two numbers the same. Since it is a unique value, hence we need neither statement I nor statement II to answer the question.



  1. Let PQRS be quadrilateral. Two circle 01 and 02 are inscribed in triangles PQR and PSR respectively. Circle 01 touches PR at M and circle 02 touches PR at N. Find the length of MN.
    I. A Circle is inscribed in the quadrilateral PQRS.
    II. The radii of the circles 01 and 02 are 5 and 6 units respectively.











  1. View Hint View Answer Discuss in Forum

    Statement I alone is sufficient.
    Statement II alone is not sufficient, for we can have more then one value of MN possible.

    Correct Option: A

    Statement I alone is sufficient.
    Statement II alone is not sufficient, for we can have more then one value of MN possible.