NBT Academic and Quantitative Literacy Flashcards

A city's municipal budget increased by 50% in Year 1, then decreased by 33⅓% in Year 2. After both changes, how does the budget compare to its original value?

Answer: It is exactly equal to the original value

Increasing by 50% means multiplying by 1.5. Decreasing by 33⅓% means multiplying by 2/3 (since 33⅓% = 1/3). So: 1.5 × (2/3) = 3/2 × 2/3 = 1.0 — exactly the original. The intuitive trap is assuming a 50% gain and a ~33% loss leaves a net positive, but the specific fraction 1/3 is the exact inverse of ×1.5.

A university reports that its Law graduates earn an average (mean) salary of R1,200,000 per year. A prospective student concludes this figure reflects what a typical Law graduate earns. Which statistical concern most directly undermines the reliability of that specific conclusion?

Answer: The mean is disproportionately pulled upward by a small number of exceptionally high earners, making it unrepresentative of the typical graduate

Salary distributions are heavily right-skewed — a handful of partners at top firms can earn R10M+, dragging the mean far above what most graduates earn. The median salary would be far more representative of the 'typical' outcome. While the other options raise valid concerns, they do not directly address why this particular figure misrepresents the typical graduate's experience.

Read the following passage: 'Despite widespread belief that multitasking enhances productivity, cognitive research consistently demonstrates the opposite. Studies show that switching between tasks — even briefly — incurs a switching cost that reduces overall efficiency. Yet in modern workplaces, employees are routinely evaluated on their ability to handle multiple priorities simultaneously, rewarding behaviour that demonstrably undermines their performance.' Which of the following can be most directly inferred from the passage?

Answer: Workplace evaluation criteria may conflict with empirically supported practices

The passage explicitly states that workplaces reward multitasking behaviour while research shows it reduces performance — a direct contradiction between evaluation practice and evidence. Option A goes beyond the text (employers could be aware but choose to ignore the research). Option C introduces 'permanent impairment,' which is not stated. Option D inverts the logic — those who refuse to multitask would likely be rated lower, but the passage doesn't state this as a conclusion.

A factory produces 480 units in 8 hours using 6 workers. Management reduces the workforce by one-third and extends the shift by 25%. Assuming each worker's output rate per hour remains constant, what is the new total output?

Answer: 400 units

Original rate: 480 ÷ (8 hours × 6 workers) = 10 units per worker per hour. New workforce: 6 × (1 − 1/3) = 4 workers. New shift: 8 × 1.25 = 10 hours. New output: 10 units/worker/hr × 4 workers × 10 hours = 400 units. The two changes partially offset each other but do not cancel out completely.

An academic essay arguing for stricter sugar taxes includes a paragraph that explicitly acknowledges the disproportionate financial burden such taxes place on low-income households. What is the PRIMARY rhetorical function of this acknowledgment within the essay?

Answer: To strengthen the essay's credibility by demonstrating awareness of counterarguments, making the overall argument more persuasive

Acknowledging a counterargument (a rhetorical move called concession) is a deliberate strategy to build ethos — it shows the author has considered opposing views and is not presenting a one-sided case. This typically makes the core argument more persuasive, not weaker. Option A misreads concession as defeat. Options B and D project specific policy or logical positions that are not implied by the act of acknowledgment alone.

Student A scores 68% on a test weighted at 30% of the final mark and 91% on a project weighted at 70%. Student B scores 82% on both assessments. Which student achieves the higher final mark, and what is the difference?

Answer: Student A, by 1.7 percentage points

Student A: (0.68 × 0.30) + (0.91 × 0.70) = 0.204 + 0.637 = 0.841 = 84.1%. Student B: (0.82 × 0.30) + (0.82 × 0.70) = 0.82 = 82.0%. Student A wins by 84.1 − 82.0 = 2.1 percentage points. Wait — recalculating: 0.68×0.30 = 0.204; 0.91×0.70 = 0.637; total = 83.7%. Student B = 82.0%. Difference = 1.7 percentage points. Student A's strong performance on the heavily weighted project overcomes the weaker test score.