Bradley owns b video game cartridges. If Bradleyâ€™s total is quarter the total owned by Andrew and four times the total owned by Charlie, how many video game cartridges do the three of them own altogether, in terms of b?
Choose the most appropriate option.
A) 16/3)b B) 17/4)b C) 13/4)b D) 21/4)b E) 7/12)b
Step 1: Categorize the problem   This problem is testing basic algebra and equations, with an extra layer of complexity by having variables in the answer choices.   Step 2: Think like the test maker   What is the key detail or key details in the problem? The key detail to immediately recognize is that the problem gives you Andrew and Charlieâ€™s totals in relation to Bradleyâ€™s total rather than giving you Bradleyâ€™s total in relation to the other two; and then the problem asks you to solve the problem in terms of b. This means that you have to relate Andrew and Charlieâ€™s values in relation to Bradleyâ€™s total. The test maker is attempting to force you to structure the problem in the opposite way that most people are used to structuring information. By gaining this insight, it makes it easier to solve the problem.   Step 3: Solve the problem   b = Bradleyâ€™s total   4b = Andrewâ€™s total   (1/4)b = Charlieâ€™s total   Add each total   b + 4b+ (1/4)b = 5b + (1/4)b = (20/4)b + (1/4)b = (21/4)b   Therefore,choose 21/4)b.
<result>D</result>
Bradley owns b video game cartridges. If Bradleyâ€™s total is quarter the total owned by Andrew and four times the total owned by Charlie, how many video game cartridges do the three of them own altogether, in terms of b?