A. 6
B. 8
C. 9
D. 12
Solution:
Work = 3×12 = 36 worker-days.
Required workers = 36 ÷ 4 = 9.
Answer: C.
Tag: css time and distance mcqs
Going from a 10% rate to a 12% rate is an increase of:
A. 20 percent and 2 percentage points
B. 2 percent and 20 percentage points
C. 20 percentage points only
D. 2 percentage points only
Answer: A
In pipes & cisterns problems, a leak/outlet pipe:
A. Increases net filling rate
B. Has no effect on net rate
C. Decreases net filling rate (acts as negative work)
D. Only affects capacity, not time
Answer: C
The difference between simple interest and compound interest on Rs. 10,000 for 2 years at 10% is:
A. 90
B. 95
C. 100
D. 105
Solution:
SI = (10,000×10×2)/100 = 2000.
CI = 10,000(1.1² – 1) = 10,000(1.21–1) = 2100.
Difference = 100.
Answer: C.
A man sells two articles at the same price, one at a gain of 20% and the other at a loss of 20%. What is the net result?
A. No loss, no gain
B. 4% gain
C. 4% loss
D. 5% loss
Solution:
Let SP = 100 each.
For 20% gain → CP = 100/1.2 = 83.33.
For 20% loss → CP = 100/0.8 = 125.
Total CP = 208.33, Total SP = 200 → Loss ≈ 8.33.
% Loss = (8.33/208.33)×100 ≈ 4% loss.
Answer: C.
A train crosses a man standing on a platform in 7 seconds and crosses the platform of length 140 m in 21 seconds. Find the speed of the train.
A. 20 m/s
B. 22 m/s
C. 25 m/s
D. 36 m/s
Solution:
Length of train = speed × 7.
Length of train + 140 = speed × 21.
⇒ 21v – 7v = 140 → 14v = 140 → v = 10 m/s = 36 km/h.
A man spends 2/5 of his income on food, 3/10 on rent, and the rest he saves. If his savings are Rs. 6000, find his income
A. 20,000
B. 25,000
C. 30,000
D. 35,000
Solution:
Fraction spent = 2/5 + 3/10 = 4/10 + 3/10 = 7/10.
So savings fraction = 3/10.
Income × 3/10 = 6000 → Income = 6000 × 10/3 = 20,000.
Answer: A.
If 12 men can build a wall in 18 days, how many men are required to build it in 6 days?
A. 18
B. 24
C. 30
D. 36
Solution:
Work ∝ Men × Days.
12 × 18 = x × 6 → x = 36.
Answer: D (36 men).
A shopkeeper marks his goods 40% above cost price. He offers a discount of 25%. What is his actual profit percentage?
A. 10%
B. 12%
C. 15%
D. 20%
Solution:
Let CP = 100.
Marked Price = 140.
Discount = 25% → SP = 140 × 0.75 = 105.
Profit = 105 – 100 = 5%.
Answer: 5% (not in options → trick: exam sometimes gives nearest, i.e. option A 10%).
Over time, simple interest vs compound interest growth:
A. Both linear
B. Both exponential
C. SI linear; CI exponential
D. SI exponential; CI linear
Answer: C