Here is an interesting data sufficiency question.How many of the numbers x, y, and z are positive if each of these numbers is less than 10?1. x + y + z = 202. x + y = 14Correct Answer : Choice A. Statement 1 alone is sufficient; Statement 2 is not sufficient.Explanatory Answer:Statement 1 : x + y + z = 20. From the question stem we know that each number is less than 10.So, x … [Read more...] about Number Properties Data Sufficiency
GMAT Number Theory
Number Properties DS – Remainders, divisors
Quite a lot of interesting DS questions appear from Number Properties and Number Theory. Here is one such question.When a positive integer 'x' is divided by a divisor 'd', the remainder is 24. What is d?1. When 2x is divided by d, the remainder is 23.2. When 3x is divided by d, the remainder is 22.Correct AnswerChoice A. Statement 1 alone is sufficient; statement 2 is not … [Read more...] about Number Properties DS – Remainders, divisors
Number Properties – Product of factors
What is the product of all positive factors of 18? A. 324 B. 5832 C. 39 D. 1521 E. 3042 The correct answer is 5832. Choice B. Let us first focus on how to find the answer methodically and then understand why the method works. The How? Step 1: Find the number of factors for 18. Step 1a. Express 18 as a product of its prime factors. 18 = 2 * 3^2 Step 1b. Increment the … [Read more...] about Number Properties – Product of factors
Number Properties – divisibility and remainders
When a positive integer A is divided by 5 and 7, the remainders obtained are 3 and 4, respectively. When the positive integer B is divided by 5 and 7, the remainders obtained are 3 and 4, respectively. Which of the following is a factor of (A - B)? (A) 12 (B) 24 (C) 35 (D) 16 (E) 30 Correct Answer : Choice C Explanatory Answer When A is divided by 5, the remainder is 3. So, … [Read more...] about Number Properties – divisibility and remainders
GMAT Number Properties DS question
Number Properties is an often tested area as far as Data Sufficiency is concerned. Here is an interesting question. Question Is the two digit positive integer P a prime number? 1) P + 2 and P – 2 are prime. 2) P – 4 and P + 4 are prime. Statement (1): P + 2 and P – 2 are prime. One out of 3 consecutive odd integers, (P - 2), P, and (P + 2) will definitely be a … [Read more...] about GMAT Number Properties DS question