Liam is pulled over for speeding just as he is arriving at work. He
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27 Apr 2021, 00:04
Considering the actual driving speed as x and t to be actual time to cover that distance
30 = x* (t-4), where t is in minutes and x is m/min
Next equation will be
30 = S * t , where S is ideal driving speed to cover 30 miles.
Where S = (x - 5/60) m/min
Dividing both the equation
we get t = 48x
By putting this value back to 1st equation
we get 48x^2 - 4x - 30 =0
Solving would give 80/96 miles per minute
By multiplying by 60
We get 50m/h
Hence A should be the answer