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Question
A car driver increases the average speed of his car by 3 km/hr every hour. The total distance travelled in 7 hours if the distance covered in the first hour was 30 km, is
Options
266 km
273 km
280 km
287 km
Solution
273 km
Explanation:
Speed of car in 1st hours `30/1` = 30 km/h
Speed of the car in 2nd hour = 30 + 3 = 33 km/hr
Distance covered in 2nd hour = 33 km
Speed of the car in 3rd hour = 33 + 3 = 36 km/hr
Distance covered in 3rd hour = 36 km
Similarly, distance travelled in 4th, 5th, 6th and 7th hours are 39 km, 42 km, 45 km, and 48 km
total distance travelled in 7 hours
= 30 + 33 + 36 + 39 + 42 + 45 + 48 = 273 km
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