Part A
(85 km)/(51 min) = (x km)/(60 min)
85/51 = x/60
85*60 = 51x
5100 = 51x
51x = 5100
x = 5100/51
x = 100
Answer: 100 km
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Part B
510 m = 0.510 km
(85 km)/(51 min) = (0.510 km)/(x min)
85/51 = 0.510/x
85x = 51*0.510
85x = 26.01
x = 26.01/85
x = 0.306
This represents the number of minutes. Multiply by 60 to get the number of seconds
0.306 min = 0.306*60 = 18.36
Answer: 18.36 seconds