A was travelling from point X to point Y. He increased
his speed by 12 km/h after every hour. He reached his destination in 24 hours. If his initial speed was 26 km/h, then what was his average speed in the whole journey?
A124 km/hCorrect AnswerIncorrect Answer
B134 km/hCorrect AnswerIncorrect Answer
C164 km/hCorrect AnswerIncorrect Answer
D144 km/hCorrect AnswerIncorrect Answer
Solution
Total distance travelled by A = (24/2) × {2 × 26 + (24 – 1) × 12} = 12 × (52 + 276) = 3936 km Required average speed = 3936/24 = 164 km/h