Data Sufficiency : Introduction
Data Sufficiency Example Problems with Explanations
1. How is Manik related to Nisha ?
- Manik is the only son of Nisha's mother - in - law.
- Ritu is Manik's only sister.
Solution : From 1, we know that Manik is the only son of Nisha's mother-in-law i.e., Manik is Nisha's husband. However, the relation between Manik and Nisha cannot be deduced from 2. So, 1 alone is sufficient to answer the given question.
2. What day is the fourteenth of a given month ?
- The last day of the month is a Wednesday.
- The third Saturday of the month was seventeenth.
Solution : Clearly, statement 2 reveals that 17th was a Saturday and therefore, 14th was Wednesday.
3. What is Suman's rank from the top in the class of 40 students ?
- Reena is 4 ranks below Suman and is thirty-first from the bottom.
- Anuj is two ranks above Suman and is thirty-seventh from the bottom.
Solution : From 1, we conclude that Suman has (1 + 3 + 30) = 34 Students below her in rank, namely Reena, 30 students below Reena and 3 students between Suman and Reena. Thus, there are [40 - (34 + 1)] = 5 students above Suman in rank. So, suman is 6th from the top. From 2, we conclude that Anuj is 37th from the bottom i.e., 4th from the top. Since Anuj is two ranks above Suman, so Suman is 6th from the top. Thus, either 1 alone or 2 alone is sufficient to answer the given question.
4. What does 'ta' mean in a code language ?
- 'Pa ta ja' means 'over and above' in that code language.
- 'ho ka pa' means 'come over here' in that code language.
Solution : Clearly, to find the code for 'ta', we need to have either only 'ta' or both 'pa' and 'ja' common in 1 and 2. However, none of these conditions is fulfilled. So, the data given in both 1 and 2 together is also not sufficient to answer the given question.
5. Among D, F, J, P and A who reached office last ?
- F and J reached office together.
- Only D and P reached office ahead of J.
Solution : From 1 and 2, we conclude that only D and P reached office ahead of J and thus, F. This implies that A reached last. So, the data in both 1 and 2 together are required to answer the given questions.
That's all for now friends. Tomorrow we shall see some more practice problems on Data Sufficiency. Happy Reading :)
Shared by Jyothula Suryaprakash