Answers to Newsletter Practice Questions
A bullet train is scheduled to travel from Los Angeles to San Francisco at an average speed of 225 mph over 400 miles. If on the first 90 miles of the journey there is construction on the track, limiting the train to 125 mph, which of the following is closest to the average speed for the balance of the journey?
A) 250 mph
B) 264 mph
C) 275 mph
D) 293 mph
E) 325 mph
We must utilize the equation distance = rate * time. In fact we need to use it 3 times. First 400 miles = 225mph * total time. Total time = 1.77 hrs. Save this number. Then the first “slower” leg: 90 miles = 125 mph * time1. Time1= .72 hours. Then, total time = time1 + time2. So 1.77 = .72 + time2. Time 2 = 1.057 hours. Finally, the last leg: the remaining distance = rate2 * time2. So 310 = rate2 * 1.057. Rate2 = 293 mph.
Consider the following excerpt from Richard Florida’s The Great Reset:
The costs are astounding. In Los Angeles, congestion eats up more than 485 million working hours a year; that’s seventy hours, or nearly two weeks, of full-time work per commuter. In D.C., the time cost of congestion is sixty-two hours per worker per year. In New York it’s forty-four hours. Average it out, and the time cost across America’s thirteen biggest city-regions is fifty-one hours per worker per year. Across the country, commuting wastes 4.2 billion hours of work time annually—nearly a full workweek for every commuter. The overall cost to the U.S. economy is nearly $90 billion when lost productivity and wasted fuel are taken into account. At the Martin Prosperity Institute, we calculate that every minute shaved off America’s commuting time is worth $19.5 billion in value added to the economy. The numbers add up fast: five minutes is worth $97.7 billion; ten minutes, $195 billion; fifteen minutes, $292 billion.
The passage most strongly suggests that researchers at the Martin Prosperity Institute share which assumption?
A) Employees who work from home are more valuable to their employers than employees who commute.
B) Employees whose commutes are shortened will use the time saved to do additional productive work for their employers.
C) Employees can conduct business activities, such as composing memos or joining conference calls, while commuting.
D) Employees who have lengthy commutes tend to make more money than employees who have shorter commutes.
We must remember a fundamental rule in SAT Reading Comprehension: “Reference, not Inference”. I.e. we must base our answer as closely on the text as possible. In the final two sentences of the paragraph, we see a “conversion”: “every minute shaved off America’s commuting time is worth $19.5 billion in value added to the economy.” We must ask, without making any assumptions, how is time saved equated to value added to the economy? It must be by additional work being done in lieu of commuting, hence choice B.
Genevieve is the designer of a combination lock. To open the lock, a user must turn a small wheel to capture a three number combination in the correct order (example: 38, 4, 15). The wheel is numbered 0 to 39, inclusive. If no two numbers are allowed to be repeated in a successful combination, how many potential combinations can Genevieve’s lock have?
The word “combination” is a trap here. More important are the words “in the correct order”, which make this a permutation problem that is more easily tackled using the “mannequin problem” method. Since order matters (in the example from the problem, 38, 4, 15 was a successful combination but 15, 4, 38 would not be successful), we lay out 3 “spots”: ____ ____ ____. We then ask, how many choices do I have for the first spot? Since 0 to 39 inclusive means 40 possible choices, we put “40” in the first spot: _40_ ___ ____. We then ask, after a number is taken, how many choices do I have for the second spot? 39, then we do this again for the third spot.Then we multiply, so: _40_ * _39_ * _38_ = 59,280.
Choose the alternative you consider best to replace the underlined portion.
I am not a fan of the actors who the academy nominated for the prize this year.
A) NO CHANGE
B) who, the academy,
C) whom the academy
D) whom, the academy,
“Who” is a subject pronoun and “whom” is an object pronoun. In the underlined portion of the sentence, “who the academy nominates”, we see “the academy” is the subject of “nominates”. Subject pronouns (like “who”) should only be used in subjects; everywhere else we use object pronouns. The “who” from the underlined portion is thus in the object of the sentence and should therefore be corrected to “whom”.