a car traveling at a certain constant speed takes 2 secs longer to travel 1km than it would to travel 1km at 75kph. at what speed in kph is the car travelling?
a 71.5
b 72
c 72.5
d 73
e 73.5
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Not sure if this is the quickest way -
If the car is travels at 75Km/hr, it would take 48 sec (Dist/Speed or 1/75; convert hr into sec.) to cover 1 Km
But it is traveling at xKm/hr and takes 2 sec. more than if it traveled at 75km/hr; so it takes 50 sec.
D=1Km;
T=50/60*60 hr or 1/72 hr
So, S=D/T or 1/(1/72) or 72Km/hr
Ans:B
If the car is travels at 75Km/hr, it would take 48 sec (Dist/Speed or 1/75; convert hr into sec.) to cover 1 Km
But it is traveling at xKm/hr and takes 2 sec. more than if it traveled at 75km/hr; so it takes 50 sec.
D=1Km;
T=50/60*60 hr or 1/72 hr
So, S=D/T or 1/(1/72) or 72Km/hr
Ans:B
