In a parking area, the total number of wheels of all the cars (four-wheelers) and scooters/motorbikes (two-wheelers) is 100 more than twice the number of parked vehicles. The number of cars parked is
- (a) 35
- (b) 45
- (c) 50 ✓ UPSC's answer
- (d) 55
Why the answer is (c)
• Let there be c cars and s two-wheelers.
• Wheels = 4c + 2s; twice the number of vehicles = 2c + 2s.
• The difference is 4c + 2s − (2c + 2s) = 2c, and this equals 100.
• So c = 50.
• Hence option (c).
Why the other options are wrong
- (a) 35
- 35 cars would make the difference 70, not 100.
- (b) 45
- 45 cars would make the difference 90, not 100.
- (d) 55
- 55 cars would make the difference 110, not 100.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2015, held on 23 August 2015. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.