Data Sufficiency 2
Practice and master this topic with our carefully crafted questions.
Each of the questions given below consists of a question followed by three statements. You have to study the question and the statements and decide which of the statement(s) is/are necessary to answer the question.
I. Let the present ages of Tanya and Rahul be 3x years and 4x years.
II. After 5 years, (Tanya's age) : (Rahul's age) = 4 : 5.
III. (Rahul's age) = (Tanya's age) + 5.
| From I and II, we get | 3x + 5 | = | 4 | . This gives x. |
| 4x + 5 | 5 |
Tanya's age = 3x can be found. Thus, I and II give the answer.
From I and III, we get 4x = 3x + 5. This gives x.
Tanya's age = 3x can be found. Thus, I and III give the answer.
From III : Let Tanya's present age be t years.
Then Rahul's present age = (t + 5) years.
Thus,
| From II and III, we get : | t | = | 4 | . This gives t. |
| t + 5 | 5 |
Thus, II and III give the answer.
Correct answer is (E).
II. Let the present ages of Arun and his son be 11x and 6x years respectively.
I. 5 years ago, Arun's age = 2 x His son's age.
| III. 5 years hence, | Arun's Age | = | 12 |
| Son's age | 7 |
Clearly, any two of the above will give Arun's present age.
Correct answer is (D).
I. Let Ravi's present age be x years.
Then, his father's present age = 2x years.
| II. After 5 years, | Ravi's age | = | 6 |
| Father's age | 11 |
III. Ravi is younger than his brother.
| From I and II, we get | x + 5 | = | 6 | . |
| 2x + 5 | 11 |
This gives x, the answer.
Thus, I and II together give the answer. Clearly, III is redundant.
Correct answer is (A).