IIT JEE Practice Question and Answer
8Q: If the positions of the first and the third digit within each number are interchanged, which of the following will be the third digit of the second lowest number ? 987, 514, 658, 487, 404, 269 4602 05b5cc6f8e4d2b4197774f01d
5b5cc6f8e4d2b4197774f01d- 18false
- 29false
- 32false
- 44true
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Answer : 4. "4"
Explanation :
Answer: D) 4 Explanation: According to the question, after the position of the first and third digit interchanged new numbers are 789, 415, 856, 784, 404, 962 962, 856, 789, 784, 404, 415Here the second lowest number is 404 and the last digit of it is '4'.
Q: A flagstaff 17.5 m high casts a shadow of length 40.25 m. What will be the height of a building, which casts a shadow of length 28.75 m under similar conditions ? 1576 15b5cc6f4e4d2b4197774f013
5b5cc6f4e4d2b4197774f013- 114 cmfalse
- 213.5 cmfalse
- 312.5 cmtrue
- 411.4 cmfalse
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Answer : 3. "12.5 cm"
Explanation :
Answer: C) 12.5 cm Explanation: Let the required height of the building be x meter More shadow length, More height(direct proportion) Hence we can write as (shadow length) 40.25 : 28.75 :: 17.5 : x⇒ 40.25 × x = 28.75 × 17.5⇒ x = 28.75 × 17.5/40.25= 2875 × 175/40250= 2875 × 7/1610= 2875/230= 575/46= 12.5 cm
Q: Complete the missing number in the given series. 5, 20, 76, (—), 448 3646 05b5cc6f4e4d2b4197774f009
5b5cc6f4e4d2b4197774f009- 1185false
- 2225true
- 3415false
- 4232false
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Answer : 2. "225"
Explanation :
Answer: B) 225 Explanation: The series follows the following pattern 5 X 5 – 5 = 20 20 X 4 – 4 = 76 76 X 3 – 3 = 225 225 X 2 – 2 = 448 Hence, the term 225 denoted by (d) completes the series
Q: A can complete a work in 12 days with a working of 8 hours per day. B can complete the same work in 8 days when working 10 hours a day. If A and B work together, working 8 hours a day, the work can be completed in --- days ? 789 05b5cc6f4e4d2b4197774f00e
5b5cc6f4e4d2b4197774f00e- 151/24false
- 287/5false
- 357/12false
- 460/11true
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Answer : 4. "60/11"
Explanation :
Answer: D) 60/11 Explanation: A can complete the work in 12 days working 8 hours a day => Number of hours A can complete the work = 12×8 = 96 hours => Work done by A in 1 hour = 1/96 B can complete the work in 8 days working 10 hours a day => Number of hours B can complete the work = 8×10 = 80 hours => Work done by B in 1 hour = 1/80 Work done by A and B in 1 hour = 1/96 + 1/80 = 11/480 => A and B can complete the work in 480/11 hours A and B works 8 hours a day. Hence total days to complete the work with A and B working together = (480/11)/ (8) = 60/11 days
Q: A box contains 4 different black balls, 3 different red balls and 5 different blue balls. In how many ways can the balls be selected if every selection must have at least 1 black ball and one red ball ? 2340 05b5cc6f4e4d2b4197774f004
5b5cc6f4e4d2b4197774f004- 124 - 1false
- 22425-1false
- 3(24-1)(23-1)25true
- 4Nonefalse
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Answer : 3. "(24-1)(23-1)25"
Explanation :
Answer: C) C Explanation: It is explicitly given that all the 4 black balls are different, all the 3 red balls are different and all the 5 blue balls are different. Hence this is a case where all are distinct objects. Initially let's find out the number of ways in which we can select the black balls. Note that at least 1 black ball must be included in each selection. Hence, we can select 1 black ball from 4 black ballsor 2 black balls from 4 black balls.or 3 black balls from 4 black balls.or 4 black balls from 4 black balls. Hence, number of ways in which we can select the black balls = 4C1 + 4C2 + 4C3 + 4C4= 24-1 ........(A) Now let's find out the number of ways in which we can select the red balls. Note that at least 1 red ball must be included in each selection. Hence, we can select 1 red ball from 3 red ballsor 2 red balls from 3 red ballsor 3 red balls from 3 red balls Hence, number of ways in which we can select the red balls= 3C1 + 3C2 + 3C3=23-1........(B) Hence, we can select 0 blue ball from 5 blue balls (i.e, do not select any blue ball. In this case, only black and red balls will be there)or 1 blue ball from 5 blue ballsor 2 blue balls from 5 blue ballsor 3 blue balls from 5 blue ballsor 4 blue balls from 5 blue ballsor 5 blue balls from 5 blue balls. Hence, number of ways in which we can select the blue balls= 5C0 + 5C1 + 5C2 + … + 5C5= 25..............(C) From (A), (B) and (C), required number of ways= 2524-123-1
Q: Name the first state Police Officer of Nagaland who has been awarded one of the nations' military honour, ‘Shaurya Chakra’, in 2017 by the Government of India. 1302 05b5cc6f4e4d2b4197774eff5
5b5cc6f4e4d2b4197774eff5- 1SomviBihufalse
- 2Jong Kayifalse
- 3Nara Karomfalse
- 4AtuZumvutrue
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Answer : 4. "AtuZumvu"
Explanation :
Answer: D) AtuZumvu Explanation: For the first time since Nagaland officially gained recognition as a state, a state Police Officer AtuZumvu has been awarded one of the nations' military honour, ‘Shaurya Chakra’.
Q: Read the following information carefully and answer the questions given below it. There are five men A,B,C,D and E and six women P, Q, R, S, T and U. A, B and R are advocates, C, D, P, Q and S are doctors and the rest are teachers. Some teams are to be selected from amongst these eleven persons subject to the following conditions. A, P and U have to be together. B cannot go with D or R. E and Q have to be together. C and T have to be together. D and P cannot go together. C cannot go with Q. If the team is to consist of two male advocates, two lady doctors and one teacher, the members of team are 2201 05b5cc6f4e4d2b4197774effa
5b5cc6f4e4d2b4197774effa- 1A, P, R, S, Ufalse
- 2A, B, P, Q, Ufalse
- 3B, E, Q, R, Sfalse
- 4A, B, P, U, Strue
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Answer : 4. "A, B, P, U, S"
Explanation :
Answer: D) A, B, P, U, S Explanation: From the given information; Members Sex Profession A M Advocate Q F Doctor B M Advocate R F Advocate C M Doctor S F Doctor D M Doctor T F Teacher E M Teacher U F Teacher P F Doctor Answer (D) From option (D) A and B are two male advocates, P and S are two female doctors and u is female teacher.
Q: If the age of father is 4 years greater than the mother and 28 years greater than the son,then what is the age of the father? which one should be used to calculate the age ? 1329 05b5cc6f4e4d2b4197774eff0
5b5cc6f4e4d2b4197774eff0- 1mother/son = Non-prime numberfalse
- 2mother/son = Perfect square number A) only A alone is sufficient B) only B alone is sufficienttrue
- 3both A and B are requiredfalse
- 4A) only A alone is sufficient B) only B alone is sufficient C) both A and B are required D)false
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Answer : 2. "mother/son = Perfect square number
A) only A alone is sufficient
B) only B alone is sufficient"
Explanation :
Answer: B) only B alone is sufficient Explanation: For the given problem there are three possiblities.Father's age can be = 36, 31, 29Mother's age = 32, 27, 25Son's age = 8, 3, 1. By using only B it can be calculated.