Reading & writing · Grades 9–12
The cheaper proposal
An original passage with comprehension questions and a teacher key.
The cheaper proposal
A headline said that Proposal B would cost 20% less than Proposal A. The detailed table showed that A included equipment, installation and five years of maintenance, while B listed equipment and installation only. Both arithmetic totals were correctly added, but they covered different things. The review group requested a common five-year cost comparison and kept uncertain maintenance estimates visible. After the missing category was included, B still appeared cheaper, though by a much smaller margin. The headline had been numerically neat but incomplete.
Try it yourself
What was the main problem with the initial cost comparison?
- A percentage can never be calculated.
- Neither proposal included equipment.
- Both additions were necessarily wrong.
- The totals included different categories.
Why can correct arithmetic still support a misleading headline?
What common basis did the review group request?
- five-year costs including comparable categories
- only the proposal titles
- only equipment colour
- the number of pages
Why keep uncertain estimates visible?
What happened after the missing category was included?
- B was guaranteed to be free.
- B still appeared cheaper, but by less.
- No comparison could ever be made.
- A became identical to B in every respect.
Rewrite the headline's claim more cautiously without inventing a new percentage.
Answers and marking notes
Answers and marking notes
- The totals included different categories.
The accounting boundaries were inconsistent.
- The inputs or categories may not be comparable, so an accurate calculation answers an incomplete question.
Credit scope as well as numerical correctness.
- five-year costs including comparable categories
The same time horizon and scope support comparison.
- Readers need to see assumptions and possible variation rather than treating estimated values as exact.
Credit transparency about uncertainty.
- B still appeared cheaper, but by less.
The passage explicitly retains a smaller apparent saving.
- On a comparable five-year estimate, B appears cheaper, with the size of the saving depending on maintenance assumptions.
Credit consistent scope and uncertainty; do not invent a numerical result.
Preview material · independent educational review required. Grade bands are approximate, not official curriculum alignment.