T.C.S APTITUDE Question at J.N.T.U.A College of Engineering Pulivendula,ANDHRA PRADESH Dated on 22-10-2014
2 gears one with 12 teeth and other one with 15 teeth are engaged with each other. One teeth in smaller and one tooth in bigger are marked and initially those 2 marked teeth are in contact with each other. After how many rotations of the smaller gear with the marked teeth in the other gear will again come into contact for the first time?
a)5
b)12
c)60
d)Data insufficient

• Assume that the distance b/w gears be 1cm.
  Then the circumference of 1st gear is 12cm and 2nd gear is 15cm.
  So.
  The LCM of 12 and 15 is 60.
  So,
  1st gear has rotate 60/12=5(Smaller Gear)
  2nd gear has rotate 60/15=4(Bigger Gear)
  So,
  The answer is 5.
  
• 9 years agoHelpfull: Yes(23) No(2)
• Please Upload Some More Questions Of The Same Test..
  I have Written on 24th October.
• 9 years agoHelpfull: Yes(4) No(0)
• No information, whether the rotational speed is same or not. No information, whether size(in radius) is same or different. So, I am confused.
• 9 years agoHelpfull: Yes(1) No(1)
• M4 and Campus Gate Qustions are More enough to crack the written test
• 9 years agoHelpfull: Yes(1) No(0)
• ANS 5
  LCM of 12,15 is 60. that means at 60th teeth both will meet.
  smaller gear has 12 teeth.
  so smaller gear needs 5 rotations(60/12=5).
  second gear needs 4 rotations.(60/15=4).
• 9 years agoHelpfull: Yes(1) No(0)
• data insufficiant
• 9 years agoHelpfull: Yes(0) No(3)
• The LCM of 12 and 15 is 60.
  So,
  1st gear has rotate 60/12=5
  2nd gear has rotate 60/15=4
  ans=5
• 9 years agoHelpfull: Yes(0) No(0)
• by taking LCM we can easily find the no of rotation in which they meet
  LCM(12,15)=60
  c is ans
  
• 9 years agoHelpfull: Yes(0) No(0)
• each rotation of smaller, lags behind the meeting tooth of bigger gear by 3 teeth which has 15 teeth. So no. of rotations to meet again = 15/3 = 5
• 9 years agoHelpfull: Yes(0) No(0)