Here is an interesting quadratic equations question. Combines some concepts of number theory.Questiony = x^2 + bx + 256 cuts the x axis at (h, 0) and (k, 0). If h and k are integers, what is the least value of b?A. –32B. –256C. –255D. –257E. 0Correct Answer : Choice D. -257ExplanationThe curve cuts the x axis at (h, 0) and (k, 0). So, h and k are the roots of the quadratic … [Read more...] about Quadratic Equation : Sum of Roots
GMAT Problem Solving Practice
GMAT Equations, Number Properties
Here is an interesting question that combines linear equations and properties of numbers to get an answer.QuestionA children’s gift store sells gift certificates in denominations of $3 and $5. The store sold ‘m’ $3 certificates and ‘n’ $5 certificates worth $93 on a Saturday afternoon. If ‘m’ and ‘n’ are natural numbers, how many different values can ‘m’ take?A. 5B. 7C. 6D. … [Read more...] about GMAT Equations, Number Properties
Mean, Median & Mode – Descriptive Statistics
Here is an interesting question from Descriptive Statistics. The question tests your basic understanding of Mean, Median and ModeQuestionAn analysis of the monthly incentives received by 5 salesmen : The mean and median of the incentives is $7000. The only mode among the observations is $12,000. Incentives paid to each salesman were in full thousands. What is the difference … [Read more...] about Mean, Median & Mode – Descriptive Statistics
GMAT Descriptive Statistics : Averages
Question If the average of 5 positive integers is 40 and the difference between the largest and the smallest of these 5 numbers is 10, what is the maximum value possible for the largest of these 5 integers? A. 50B. 52C. 49D. 48E. 44 Correct Answer : Choice D. 48 ExplanationThe average of 5 positive integers is 40. i.e., the sum of these integers = 5*40 = 200 Let … [Read more...] about GMAT Descriptive Statistics : Averages
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