A dirt biker must circle a 5-mile track twice. His mean speed must be 60 mph. On his first lap, he averaged 30 mph. How fast must he travel on his second lap in order to qualify?
a)30 m.p.h. b) 60 m.p.h. c) 90 m.p.h. d) 120 m.p.h. e) none of these
A dirt biker must circle a 5-mile track twice. His mean speed must be 60 mph. On his first lap, he averaged 30 mph. How fast must he travel on his second lap in order to qualify? a)30 m.p.h. b) 60 m.p.h. c) 90 m.p.h. d) 120 m.p.h. e) none of these
Try and solve for v:
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Better yet, substitute options (c) and (d) and see if one works - obviously (a) and (b) are wrong .....