Logical Reasoning & Quantitative Techniques Flashcards

What comes next in the series: 2, 4, 8, 16, __?

Answer: 32

This is a simple geometric progression where each number is obtained by multiplying the previous number by 2. Following the pattern: 2 * 2 = 4, 4 * 2 = 8, 8 * 2 = 16. Therefore, the next number in the series is 16 * 2 = 32.

Which number is the odd one out: 3, 5, 7, 9, 11?

Answer: 9

In the given series (3, 5, 7, 9, 11), all numbers except 9 are prime numbers. A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. The number 9 is a composite number because it can be divided by 3 (in addition to 1 and 9).

Find the missing number: 6, 11, 21, 36, __

Answer: 56

Let's find the difference between consecutive numbers: 11 - 6 = 5, 21 - 11 = 10, 36 - 21 = 15. The differences are increasing by 5 each time (5, 10, 15). Therefore, the next difference should be 20. Adding 20 to the last number (36) gives 36 + 20 = 56.

Which is a valid conclusion: All lawyers are professionals. John is a lawyer.

Answer: John is a professional

This is a classic example of a deductive syllogism. The first premise states that "All lawyers are professionals." The second premise states that "John is a lawyer." Based on these two premises, it logically follows that John must also be a professional, as he belongs to the category of lawyers.

If A = 1, B = 2, ..., what is the value of 'CAB'?

Answer: 7

The numerical value of each letter is its position in the alphabet (A=1, B=2, C=3). The pattern to determine the value of 'CAB' is to multiply the value of the first letter (C) by the value of the last letter (B), and then add the value of the middle letter (A). Thus, (3 * 2) + 1 = 6 + 1 = 7.

A train runs at 60 km/h. How far will it travel in 2.5 hours?

Answer: 150 km

The problem requires calculating distance using the formula Distance = Speed × Time. Given the speed of the train is 60 km/h and the time is 2.5 hours, the distance traveled is 60 km/h * 2.5 hours. Multiplying these values gives 150 km.

Find the next letter: A, C, F, J, O, __

Answer: V

This is an alphabetical series where the gap between consecutive letters increases by one each time. A (+2 letters) C (+3 letters) F (+4 letters) J (+5 letters) O. Following this pattern, the next gap should be +6 letters. Counting 6 letters after O (P, Q, R, S, T, U), the next letter in the series is V.

A box contains 5 red, 3 blue, and 2 green balls. What is the probability of picking a red?

Answer: 1/2

To find the probability of picking a red ball, we divide the number of red balls by the total number of balls. There are 5 red balls and a total of 5 + 3 + 2 = 10 balls. Therefore, the probability is 5/10, which simplifies to 1/2.

If 5x = 40, then x = ?

Answer: 8

The equation given is 5x = 40. To solve for x, we need to isolate x by dividing both sides of the equation by 5. Dividing 40 by 5 gives 8. Therefore, x = 8.