A boy in a car notices that he can count 21 shops which are evenly spaced on a highway in one minute. If they are known to be 100 meter apart, then at what speed is the train travelling?
a) 60 kmph
b) 100 kmph
c) 120 kmph
d) 180 kmph

• Distance covered in 1 minute= Distance between 21 shops which are 100 m. apart=20*100=2000 m. (since starting and ending will not be considered) speed= dist/time
  speed=2km*60=120 km/h
• 8 years agoHelpfull: Yes(8) No(0)
• 21 shop means he will start from 1st shop(0m) so at 21st shop he must have covered d=20*100=2000m or 2km
  t=1min=1/60hr
  s=d/t=2/(1/60)=120kmph
• 8 years agoHelpfull: Yes(3) No(0)
• Ans is 120km/h since the distance after last shop should not be considered.
• 8 years agoHelpfull: Yes(1) No(0)
• 126 kmph
  
  Distance covered in 1 minute= Distance between 21 shops which are 100 m. apart=21*100=2100 m. =2.1 km
  So speed=60*2.1=126 kmph
• 8 years agoHelpfull: Yes(0) No(10)
• 21 shops are 100 meter apart from each other.
  therefore distance travelled in 1 minute = 20*100 meters=2000
  speed=dis/time
  2000/1000/1/60(converting meters in to k.m and minutes in to hours)
  =120 kmph.
• 8 years agoHelpfull: Yes(0) No(0)