How to solve: Quantitative Aptitude
What this category tests
Tests applied arithmetic under real-world framing — ratios, interest, rates, and optimization — plus, in "data sufficiency" items, judging whether given information is enough to answer a question without actually solving it.
Where this typology comes from
Word-problem arithmetic itself is ancient — comparable ratio and rate problems appear in the Rhind Mathematical Papyrus from around 1650 BCE. The "data sufficiency" format has a much more specific origin: it was added to the forerunner of the GMAT in 1961, eight years after that exam launched in 1953, specifically to test reasoning and judgment separately from raw calculation.
How to approach it
Translate a word problem into an equation immediately, keeping careful track of units as you go — most errors come from mixing units, not from the arithmetic itself. For data-sufficiency items, evaluate each piece of given information completely on its own before ever considering them together; combining them too early is the single most common mistake. For optimization or path problems, try working backward from the goal, or eliminate clearly worse options greedily, rather than checking every possibility by brute force.
Worked example
A store marks up an item by 25% over its cost price, then offers a 20% discount on the marked price during a sale. Compared to the original cost price, what is the final sale price?
- The same as the cost price ✓ Correct answer
- 5% higher than the cost price
- 5% lower than the cost price
- 10% lower than the cost price
Explanation Let the cost price be 100. A 25% markup brings the price to 125. A 20% discount on that marked price is 125 × 0.80 = 100 — exactly back to the original cost price. It's tempting to assume a 25% increase and a 20% decrease roughly cancel out, but here they cancel exactly, because the 20% discount is calculated on the larger, marked-up price, not on the original cost.
Practice Quantitative Aptitude
- Quantitative Aptitude I — Profit, Interest, Ratios & Speed · 12 questions · Difficulty 2 out of 5
- Quantitative Aptitude II — Data Sufficiency · 12 questions · Difficulty 4 out of 5
- Quantitative Aptitude III — Path Optimization · 12 questions · Difficulty 4 out of 5
- Quantitative Aptitude IV — Number Properties · 12 questions · Difficulty 3 out of 5