GRE CLASSES CHENNAI GRE CLASSES BANGALORE GRE QUESTIONS US UNIVERSITIES GRE FAQ ABOUT TOPGRE TOPGRE - GRE Practice Questions : Ratio, Percents : Question 1 Question 1 If the ratio of the ages of two friends A and B is in the ratio 3 : 5 and that of B and C is 3 : 5 and the sum of their ages is 147, then how old is B? 15 years 75 years 49 years 45 years 27 years The correct Answer is 45 years and the correct Choice is (D). Explanatory Answer The ratio of the ages of A and B is 3 : 5. The ratio of the ages of B and C is 3 : 5. B's age is the common link to both these ratio. Therefore, if we make the numerical value of the ratio of B's age in both the ratios same, then we can compare the ages of all 3 in a single ratio. The can be done by getting the value of B in both ratios to be the LCM of 3 and 5 i.e., 15. The first ratio between A and B will therefore be 9 : 15 and the second ratio between B and C will be 15 : 25. Now combining the two ratios, we get A : B : C = 9 : 15 : 25. Let their ages be 9x, 15x and 25x. Then, the sum of their ages will be 9x + 15x + 25x = 49x The question states that the sum of their ages is 147. i.e., 49x = 147 or x = 3. Therefore, B's age = 15x = 15*3 = 45 Back to Questionbank TOPGRE's next batch @ Chennai is a 10-Weekend, 60 hour program. Classes for the NEW FORMAT weekend batch will be conducted at our Nungambakkam Center from November 19, 2016. Expert Faculty. Small batch size.   Here is what our students have to say about our classroom program for GRE. Our students have made it to some of the top graduate schools in the US.   Get on top of your GRE preparation. Get free practice questions periodically sent by mail. Plus have your queries answered by peers and experts.   