distance = speed * time
time = distance / speed
let distance be d and speed be s
given
Dave drove from home to work at twice his regular speed and arrived at work 16 minutes earlier than he regularly arrives
d/2s =d/s -16/60
#1
Dave regular drives at a constant speed of 40 miles per hour.
d/80 = d/40 -16/60
solve for d ; 64/3 ; 21.3 miles
sufficient
#2
It regularly takes Dave 32 minutes to drive to work.
d/s = 32 mins
d=32s
d/2s =d/s -16
so it took 16 mins when Dave drove at twice regular speed
...
time = distance / speed
let distance be d and speed be s
given
Dave drove from home to work at twice his regular speed and arrived at work 16 minutes earlier than he regularly arrives
d/2s =d/s -16/60
#1
Dave regular drives at a constant speed of 40 miles per hour.
d/80 = d/40 -16/60
solve for d ; 64/3 ; 21.3 miles
sufficient
#2
It regularly takes Dave 32 minutes to drive to work.
d/s = 32 mins
d=32s
d/2s =d/s -16
so it took 16 mins when Dave drove at twice regular speed
...
