Quantitative Aptitude
Quantitative Aptitude
JIPMAT's Quantitative Aptitude section tests numerical fluency under time pressure: 33 multiple-choice questions in a 100-question, 120-minute paper, scored +4 for a correct answer and −1 for a wrong one. The syllabus is Class 10 level, but the difficulty comes from combining topics in one question.
Core rules to keep ready
- Percentage change: successive changes of a% and b% give a net change of a + b + ab/100. A 20% rise then a 10% fall is 20 − 10 − 2 = 8% net rise.
- Ratio and proportion: convert every quantity to a common base before comparing. Use the unitary method only after the base is fixed.
- Time and work: if A finishes in x days and B in y days, together they take xy/(x + y) days. Efficiency is inversely proportional to time.
- Speed–distance–time: average speed for equal distances is 2xy/(x + y), not (x + y)/2.
- Interest: SI = PRT/100; CI = P(1 + R/100)^T − P. For half-yearly compounding, halve R and double T.
- Mensuration: changing a linear dimension by factor k changes area by k² and volume by k³.
Worked example
A rectangle's length increases by 20% and breadth falls by 10%. What is the area change? Take L = 100, B = 100, area = 10,000. New L = 120, new B = 90, new area = 10,800. Change = 800/10,000 = 8% increase. Shortcut: 20 + (−10) + (20)(−10)/100 = 8%.
Traps that cost marks
Discount is usually calculated on marked price, not cost price. Do not average speeds arithmetically. Watch units (cm vs m, minutes vs hours). In percentages, “percentage points” and “percent” differ. With negative marking, blind guessing is costly; eliminate first.