Showing 411–420 of 500 questions
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A shopkeeper marks an item at Rs. 500. He gives a discount of 20% and still makes a profit of 25%. What is the cost price?
ARs. 320
BRs. 400
CRs. 350
DRs. 380
Correct Answer:
A. Rs. 320Explanation:
Selling Price = 500 × 80/100 = Rs. 400. If profit is 25%, then CP = 400 × 100/125 = Rs. 320
Two pipes A and B can fill a tank in 12 hours and 15 hours respectively. If both pipes are opened together, in how many hours will the tank be filled?
A6.67 hours
B5.5 hours
C7.5 hours
D8 hours
Correct Answer:
A. 6.67 hoursExplanation:
Combined rate = 1/12 + 1/15 = 5/60 + 4/60 = 9/60 = 3/20. Time = 20/3 = 6.67 hours
A train 250m long crosses a platform 150m long in 20 seconds. What is the speed of the train?
A54 km/h
B72 km/h
C45 km/h
D60 km/h
Correct Answer:
B. 72 km/hExplanation:
Distance covered = 250 + 150 = 400m. Speed = 400/20 = 20 m/s = 20 × 18/5 = 72 km/h
A boat's speed in still water is 12 km/h and the speed of current is 3 km/h. How long will it take to travel 60 km downstream?
A4 hours
B3.75 hours
C5 hours
D4.5 hours
Correct Answer:
A. 4 hoursExplanation:
Downstream speed = 12 + 3 = 15 km/h. Time = 60/15 = 4 hours
If a number is decreased by 40%, it becomes 300. What is the original number?
Explanation:
Let original number be x. x × 60/100 = 300. x = 300 × 100/60 = 500
A man buys goods for Rs. 2500 and sells them at a loss of 8%. What is the selling price?
ARs. 2300
BRs. 2200
CRs. 2400
DRs. 2100
Correct Answer:
A. Rs. 2300Explanation:
Selling Price = 2500 × 92/100 = Rs. 2300
X and Y together can complete a work in 18 days. X alone can complete it in 30 days. In how many days can Y alone complete the work?
A45 days
B38 days
C42 days
D35 days
Correct Answer:
A. 45 daysExplanation:
Y's rate = 1/18 - 1/30 = 5/90 - 3/90 = 2/90 = 1/45. Y can complete in 45 days
Rs. 1000 is invested at 10% per annum compound interest for 2 years. What is the final amount?
ARs. 1210
BRs. 1200
CRs. 1100
DRs. 1320
Correct Answer:
A. Rs. 1210Explanation:
Amount = 1000(1 + 10/100)² = 1000 × 1.1 × 1.1 = Rs. 1210
A boat goes 30 km upstream in 6 hours and 30 km downstream in 3 hours. What is the speed of the boat in still water?
A7.5 km/h
B6.5 km/h
C8 km/h
D5 km/h
Correct Answer:
A. 7.5 km/hExplanation:
Upstream speed = 30/6 = 5 km/h. Downstream speed = 30/3 = 10 km/h. Boat speed = (5+10)/2 = 7.5 km/h
A product's price increased by 25%, then decreased by 20%. What is the net change?
A0% (no change)
B+5%
C-5%
D+10%
Explanation:
Let original price = 100. After 25% increase = 125. After 20% decrease = 125 × 80/100 = 100. Net = +5% gain
