We observe that 14 is 4 more than twice 5.
The scooter's rate is 14 mph.
The bicycle's rate is 5 mph.
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time = distance/rate
14/(2b +4) = 5/b . . . . . . let b represent the bicycle's speed in mi/h
14b = 10b +20 . . . . . . . .cross multiply
4b = 20 . . . . . . . . . . . . . subtract 10b
b = 5 . . . . . . . . . . . . . . . divide by 4. Same answer as above.