Q. A customer buys a laptop for $800 after a discount of 20%. What was the marked price?
A.$1000
B.$900
C.$850
D.$800
Solution
Let the marked price be x. After a 20% discount, the selling price is 0.80x. Setting this equal to $800 gives 0.80x = $800, so x = $800 / 0.80 = $1000.
Q. A customer buys two items for $120 each. If the shopkeeper gives a discount of 10% on the total bill, what is the final amount paid by the customer? (2023)
A.$216
B.$220
C.$240
D.$250
Solution
Total cost before discount = 2 * $120 = $240. Discount = 10% of $240 = $24. Final amount = $240 - $24 = $216.
Q. A customer buys two items for $240 after a discount of 10% on each. What was the total marked price of the items?
A.$250
B.$260
C.$270
D.$280
Solution
Let the total marked price be x. After a 10% discount, the selling price is 0.90x. Setting this equal to $240 gives 0.90x = $240, so x = $240 / 0.90 = $266.67, which rounds to $280.
Q. A cyclist accelerates from rest to a speed of 15 m/s. If the mass of the cyclist and the bicycle is 75 kg, what is the kinetic energy at that speed?
A.500 J
B.750 J
C.1000 J
D.1250 J
Solution
Kinetic Energy = 0.5 × mass × velocity² = 0.5 × 75 kg × (15 m/s)² = 8437.5 J.
Q. A cyclist is moving at 15 m/s and a pedestrian is walking at 5 m/s in the same direction. What is the speed of the cyclist relative to the pedestrian?
A.10 m/s
B.15 m/s
C.5 m/s
D.20 m/s
Solution
Relative speed = Speed of cyclist - Speed of pedestrian = 15 m/s - 5 m/s = 10 m/s.
Q. A cyclist is moving at 15 m/s and a pedestrian is walking at 5 m/s in the same direction. What is the relative speed of the pedestrian with respect to the cyclist?
A.10 m/s
B.5 m/s
C.20 m/s
D.15 m/s
Solution
Relative speed = Speed of pedestrian - Speed of cyclist = 5 m/s - 15 m/s = -10 m/s (10 m/s behind).
Q. A cyclist is moving at 15 m/s and passes a stationary observer. If the observer starts moving at 5 m/s in the same direction, what is the speed of the cyclist relative to the observer?
A.10 m/s
B.15 m/s
C.20 m/s
D.5 m/s
Solution
Relative speed = Speed of cyclist - Speed of observer = 15 m/s - 5 m/s = 10 m/s.
Q. A cyclist is moving at 15 m/s towards the east while a car is moving at 25 m/s towards the west. What is the relative speed of the cyclist with respect to the car?
A.10 m/s
B.15 m/s
C.40 m/s
D.25 m/s
Solution
Relative speed = Speed of cyclist + Speed of car = 15 m/s + 25 m/s = 40 m/s.