IIT JEE Practice Question and Answer
8Q: Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 4 or 15 ? 995 05b5cc741e4d2b4197774f9d6
5b5cc741e4d2b4197774f9d6- 16/19false
- 23/10true
- 37/10false
- 46/17false
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Answer : 2. "3/10"
Explanation :
Answer: B) 3/10 Explanation: Here, S = {1, 2, 3, 4, ...., 19, 20}=> n(s) = 20Let E = event of getting a multiple of 4 or 15 =multiples od 4 are {4, 8, 12, 16, 20}And multiples of 15 means multiples of 3 and 5= {3, 6 , 9, 12, 15, 18, 5, 10, 15, 20}.= the common multiple is only (15).=> E = n(E)= 6Required Probability = P(E) = n(E)/n(S) = 6/20 = 3/10.
Q: Which company is now listed to be one of the world's most valuable privately held companies ? 994 05b5cc6cee4d2b4197774e223
5b5cc6cee4d2b4197774e223- 1Space Xtrue
- 2Tata Steelsfalse
- 3Facebookfalse
- 4Applefalse
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Answer : 1. "Space X"
Explanation :
Answer: A) Space X Explanation:
Q: A tap can fill a tank in 6 hours. After half the tank is filled three more similar taps are opened. What is the total time taken to fill the tank completely ? 994 05b5cc6dae4d2b4197774e8be
5b5cc6dae4d2b4197774e8be- 14 hrs 15 minfalse
- 23 hrs 24 minfalse
- 34 hrs 51 minfalse
- 43 hrs 45 mintrue
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Answer : 4. "3 hrs 45 min"
Explanation :
Answer: D) 3 hrs 45 min Explanation: Time taken by one tap to fill half of the tank = 3 hrs. Part filled by the taps in 1 hour = 4 x 1/6 = 2/3 Remaining part = 1 - 1/2 = 1/2 2/3 : 1/2 :: 1 : p p = 1/2 x 1 x 3/2 = 3/4 hrs. i.e., 45 min So, total time taken = 3 hrs 45 min.
Q: Two trains running in opposite directions cross a pole placed on the platform in 47 seconds and 31 seconds respectively. If they cross each other in 33 seconds, what is the ratio of their speeds? 994 05b5cc764e4d2b4197774fd85
5b5cc764e4d2b4197774fd85- 11:7true
- 27:1false
- 32:3false
- 43:2false
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Answer : 1. "1:7"
Explanation :
Answer: A) 1:7 Explanation: Let the speed of the trains be x and y respectively length of train1 = 47xlength of train2 = 31yRelative speed= x + yTime taken to cross each other = 33 s=> 47x+31yx+y= 33=> (47x + 31 y) = 33(x + y)=> 14x = 2y=> x/y = 2/14 = 1/7 = 1:7
Q: Multiplicative inverse of 7? 993 05b5cc666e4d2b4197774bf08
5b5cc666e4d2b4197774bf08- 11false
- 2-1/7false
- 30false
- 41/7true
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Answer : 4. "1/7"
Explanation :
Answer: D) 1/7 Explanation: Multiplicative inverse is nothing but a reciprocal of a number. It is defined as one of a pair of numbers that when multiplied with another number equals the number 1. Multiplicative inverse or reciprocal of 7 is 7 x n = 1 => n = 1/7. Hence, Multiplicative inverse or reciprocal of 7 is 1/7.
Q: The Human Resource Development Ministry and the External Affairs Ministry launched an online verification portal ___________ to make the document verification process easier. 993 05b5cc6dbe4d2b4197774e8f0
5b5cc6dbe4d2b4197774e8f0- 1e-bharatfalse
- 2e-sanadtrue
- 3e-foriegnfalse
- 4e-verifyfalse
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Answer : 2. "e-sanad"
Explanation :
Answer: B) e-sanad Explanation: The Human Resource Development Ministry and the External Affairs Ministry launched an online verification portal to make the document verification process easier for students who planning to study abroad. The Central Board of Secondary Education’s (CBSE) academic repository of degrees and certificates “Parinam Manjusha” was also involved in the project of creating “eSanad”.
Q: Who has won the Nobel prize in "Physics" for the year 2017 ? 993 05b5cc6c2e4d2b4197774dbf0
5b5cc6c2e4d2b4197774dbf0- 1Barry Barishfalse
- 2Kip Thornefalse
- 3Rainer Weissfalse
- 4All of the abovetrue
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Answer : 4. "All of the above"
Explanation :
Answer: D) All of the above Explanation: Rainer Weiss, a professor at the Massachusetts Institute of Technology, and Kip Thorne and Barry Barish, both of the California Institute of Technology, were awarded the Nobel Prize in Physics for the discovery of ripples in space-time known as gravitational waves, which were predicted by Albert Einstein a century ago but had never been directly seen.
Q: Everyone has it and no one can lose it. What is it? 991 05b5cc69fe4d2b4197774ca1e
5b5cc69fe4d2b4197774ca1e- 1Facefalse
- 2Teethfalse
- 3Hairfalse
- 4Shadowtrue
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Answer : 4. "Shadow"
Explanation :
Answer: D) Shadow Explanation: