Mental Ability, Analytical and Logical Reasoning (UPSC) Part-IV

Total Questions: 50

31. In a parking area, the total number of wheels of all the cars (four-wheelers) and scooters/motorbikes (two-wheelers) is 100 more than twice the number of parked vehicles. The number of cars parked is [2015-II]

Correct Answer: (c) 50
Solution:Let number of cars be x

Let number of scooters / motor bikes = y

∴ Total number of parked vehicles = x + y

According to question

4x + 2y = 2(x + y) + 100

4x + 2y = 2x + 2y + 100

2x = 100

x = 50

Hence, Number of cars parked is 50.

32. The mangroves can shed tons of leaves per acre every year; fungi and bacteria break down this leaf litter and consume it, they then are consumed in turn feed small fish, which feed larger fish and birds and crocodiles. by tiny worms and crustaceans, which [2015-II]

Which among the following is the most logical inference of the above statement?

Correct Answer: (c) Mangroves have a crucial role in some of the coastal food chains.
Solution:
The passage clearly talks about the role Mangroves play in some of the coastal food chains. Other food chains - with or without Mangroves - might exist but they are not mentioned in the passage. So (c) is correct. The passage does not say that no food chain is possible without Mangroves so (a) is wrong. (b) is also wrong as the passage does not talk about Mangroves being an essential component of all marine ecosystems. Further (d) is also wrong for the same reasoning as the passage does not talk about the composition of marine flora and fauna.

33. "By liberty I mean the eager maintenance of that atmosphere in which men have the opportunity to be their best selves." [2015-II]

Which one of the following expresses the view implied in the above statement?

Correct Answer: (d) Liberty is the maintenance of conditions for the growth of human personality.
Solution:(a) is wrong because the sentence says that liberty means the eager maintenance of that atmosphere which might require restrictions as well.
(b) is wrong because if the people work only according to the law they might become good citizens but might not work to their best selves.
(c) is wrong because if people do what they desire it might lead to materialist thinking which is not the best self.
(d) is correct because with the growth of human personality the people would be their best selves.

34. Consider the figures given below: [2015-II]

To fit the question mark, the correct answer is

Correct Answer: (a)
Solution:The 'Δ' is shifting one corner to the next in the clockwise direction and each time it is getting inverted. Thus, the A should appear at the top left corner pointing upward. Rest of the elements are shifting positions in the counter clockwise direction.

35. Consider the following matrix: [2015-II]

What is the missing number at '?' in the matrix?

Correct Answer: (c) 5
Solution:In each column, let the number at the top be 'x' and the one at the bottom is  prime '(x - 1)'.The relation between columns are given by

(x) (x - 1) = 3(3 - 1) = 6

Therefore, 5(5-1)=20

36. What is the missing number 'X' of the series 7, X, 21, 31, 43? [2015-II]

Correct Answer: (c) 13
Solution:

37. Four cardboard pieces of specific shapes are shown in the following figure: [2015-II]

Which one of the following figures given can be formed by joining these pieces together?

Correct Answer: (d)
Solution:By combining the given fragment, we get figure (d).

38. In a test, a candidate attempted only 8 questions and secured 50% marks in each of the questions. If he obtained a total of 40% in the test and all questions in the test carried equal marks, how many questions were there in the test? [2015-II]

Correct Answer: (b) 10
Solution:Let marks of each question = x

According to question,

8x × 50/100 = 40    ∴ x = 40/4 = 10

∴ Total questions in test = 100/10 = 10

39. A father is nine times as old as his son and the mother is eight times as old as the son. The sum of the father's and the mother's age is 51 years. What is the age of the son? [2015-II]

Correct Answer: (d) 3 years
Solution:Let age of son = x years

Age of father = 9x

Age of mother = 8x

Now,

According to question,

8x + 9x = 51

17x = 51

x = 3 years

40. Four persons A, B, C and D consisting of two married couples are in a group. Both the women are shorter than their respective husbands. A is the tallest among the four. C is taller than B. D is B's brother. In this context, which one of the following statements is not correct? [2015-II]

Correct Answer: (c) C is taller than D.
Solution:Given, A is tallest among the four. Hence, A is male, D is also male, as D is the brother of B. Then, B and Care females. D is the husband of C. D is the shorter than A and is taller than B. Again, C is taller than B. Thus, B is the shortest among all. Hence C is taller than D is incorrect.