Practice · check as you go
Practice: See It 2: Before-and-after bars for increase and decrease
Five questions on this lesson. Every option is explained. (ppdf-proto-chsl-2026)
Pick an option and press “Check”: the right answer and why show at once. Your score comes at the end, and the clock only counts the time you take.
- Right answer +1. A wrong answer costs nothing.
- Questions come in Hindi and English. Switch any question with “Language”; questions in English only cannot switch.
- Pass mark: 3.
Sample questions with solutions
A few questions like the ones in this test, with the right answer and why.
- Question 1What is 15% of 640?
- 9.6
- 96Right answer
- 544
- 42.67
ExplanationWe know: 100% of the number = 640. We need: 15% of 640. Step 1: 1% of 640 = 640 ÷ 100 = 6.4. Step 2: 15% = 15 × 6.4 = 96. Check: 96 is a small part of 640 (less than a fifth) ✓. Faster way: 10% of 640 = 64, 5% of 640 = 32, so 15% = 64 + 32 = 96.
- Question 2A price rises from ₹480 to ₹540. What is the percentage increase?
- 11.11%
- 60%
- 12.5%Right answer
- 112.5%
ExplanationA percent increase is a percent of the OLD price. We know: old = ₹480, new = ₹540, so the rise = ₹60. Step 1: 1% of the old price = 480 ÷ 100 = ₹4.80. Step 2: 60 ÷ 4.80 = 12.5 → 12.5%. Shortcut: 60 ÷ 480 × 100 = 12.5%. Check: 12.5% of 480 = 60, and 480 + 60 = 540 ✓.
- Question 3A price rises 20% and then a further 10%. What is the total percentage increase?
- 30%
- 2%
- 28%
- 32%Right answer
ExplanationTake ₹100. Step 1: +20% of ₹100 = ₹20 → ₹120. Step 2: +10% of the NEW ₹120 = ₹12 → ₹132. Compare with ₹100: ₹32 more = 32%. Shortcut: 20 + 10 + (20 × 10) ÷ 100 = 32%. Check: 1.2 × 1.1 = 1.32 ✓.
- Question 4What is 45% of 260?
- 11.7
- 143
- 117Right answer
- 104
ExplanationWe know: 100% = 260. We need: 45% of 260. Step 1: 1% of 260 = 2.6. Step 2: 45% = 45 × 2.6 = 117. Check: 45% is a bit less than half, and 117 is a bit less than half of 260 (130) ✓. Faster way: 50% of 260 = 130, 5% of 260 = 13, so 45% = 130 − 13 = 117.
- Question 5A bus fare rises from ₹250 to ₹300. What is the percentage increase?
- 16.67%
- 50%
- 120%
- 20%Right answer
ExplanationA percent rise is a percent of the OLD fare. Rise = 300 − 250 = ₹50. Step 1: 1% of the old fare = 250 ÷ 100 = ₹2.50. Step 2: 50 ÷ 2.50 = 20 → 20%. Shortcut: 50 ÷ 250 × 100 = 20%. Check: 20% of 250 = 50, and 250 + 50 = 300 ✓.