Hi Winter,
I am posting the answer to each of your question.
1. Given that Purchase price = $150. Let the selling price be x. Therefore, x = 150 + 40% of x ( note that markup price is 40% of the selling price).
So, solving the above equation we get x=$250. Now, Profit = selling price - purchase price. Hence, Profit= $250 - $ 150 = $100. Answer: E
2. For these types of questions you should first add the total no of scores, which in this case is 73. Since, this is an odd number the median will be (73 + 1) / 2 = 37. This means that the 37th score is the median. Now, see the intervals given. For Interval (50-59), (60-69) and (70-79) the corresponding scores add up to be 2 + 10 + 16 = 28. Since, we need the 37th number and number of scores for interval (80-89) is 27, we are sure that the 37th number falls in (80-89) interval. Hence, C.
3. For such questions all you need to do is replace x with a and b and a+b while calculating f(a) and f(b) and f(a+b) respectively.
only choice E, f(x) = -3x fits our condition because f(a)= -3a, f(b)=-3b. So, f(a) + f(b)= -3a -3b and f(a+b)=-3(a+b) = -3a -3b.
4. As this is an arithmetic sequence with first term as 23 and common difference as -3, simply use the formula Tn = a + (n-1)d, where a is the first term and d is the common difference. So, -4 = 23 + (n-1)* -3. Working this out you can find n=10. Hence, C.
Hope that answers your questions. Let me know if anything is not clear.
Parul Oberai is a content expert for GMATLounge. She has a lot of experience helping GMAT students to be more efficient in solving quantitative problems. She can be reached at
https://gmatlounge.com/ .
