erikvm wrote:

Larissa and Steve each drove the same distance from City X to City Y in separate cars. Did it take longer for Larissa than for Steve to complete this trip?

(1) On this trip, Larissa's average speed was 80 kilometers per hour and Steve's average speed was 85 kilometers per hour

(2) On this trip, Larissa and Steve each drove 68 kilometers

See spoiler for my question

OA is A, but can this question actually be answered? Nowhere is it mentioned that they kept a constant speed. Let's say the distance was 80 and Larissa kept a constant speed of 80kph. She would spend 1 hour driving, but if Steve spent the first 79 km driving 1 kph and then the remaining 1 km at 6799 kph, thus keeping his average speed at 85kph but he would clearly spend more time driving? If however, Steve also kept a constant speed of 85kph, he would definitely complete the distance in shorter time

Hi erikvm,

In statement 1, it's mentioned that

On this trip, Larissa's average speed was 80 kilometers per hour and Steve's average speed was 85 kilometers per hour which should be interpreted that whether they had constant speed or variable speed at every moment during their travel, finally they have been able to manage the average speeds of 80 and 85 Km/Hr.

Please Note: You may drive from your home to office at 10 Km/hr and office to home at 20 km/h at constant speed but the average speed of the entire journey will be 40/3 km/hr whereas you have never driven at 40/3 km/h at any point of time in your journey. So average speed is the reflection of Total Distance travelled and total time taken

Average Speed = Total Distance / Total Time

i.e. Total Time = Total Distance / Average Speed

i.e. If distance travelled by two riders are equal then Ratio of Time will be reciprocal of ratio of their respective Average Speeds
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