A person travels equal distances at speeds of 2 km/h, 4 km/h, 5 km/h, 7 km/h and 12 km/h, and takes a total of 1485 minutes. What is the total distance (in km) travelled (to the nearest integer)?
105
The correct answer is 105.
So, \frac{5}{V_{avg}} = \frac{494}{420} = \frac{247}{210} V_{avg} = \frac{5 \times 210}{247} = \frac{1050}{247} km/h. Total Distance = Average Speed \times Total Time Total Distance = \frac{1050}{247} \times \frac{99}{4} km Let's check if this matches our previous result: \frac{1050 \times 99}{247 \times 4} = \frac{103950}{988} Is \frac{103950}{988} equal to \frac{51975}{494}? Yes, because \frac{103950}{988} = \frac{51975 \times 2}{494 \times 2} = \frac{51975}{494}. So, the average speed approach also leads to the same total distance calculation, confirming our result.
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