IIT JEE Practice Question and Answer
8Q: Maheshwari wants to buy 7 floors in an 68 storied building whose numbering stars from 1 upto 68. But she has to follow certain rules which are as follows : 1) None of the floor should be a prime number 2) None of the digit of the floor should be a prime number 3) Maheshwari cannot buy the 1st floor as it is being assigned to the architect. So how many options are left with Maheshwari to buy the floors ? 1083 05b5cc709e4d2b4197774f2a8
5b5cc709e4d2b4197774f2a8- 111false
- 217true
- 313false
- 419false
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Answer : 2. "17"
Explanation :
Answer: B) 17 Explanation: Since floor starts form the 1 therefore 2 will be the 1st floor.Form 1 to 10 only 4,6,8,9,10 are not prime.Form 11 to 20 only 14 ,16,18 are not prime also non of their digits are prime.From 21 to 30 each number has a prime number so it must no be consider.In between 40 to 49 we have to consider only 40,44,46,48,49.50 to 59 follow either of the condition so we have too neglect it.In between 60 to 68 60,64,66,68.total option = 17.
Q: Consider 5 independent Bernoulli’s trials each with probability of success p. If the probability of at least one failure is greater than or equal to 31/32 , then p lies in the interval ? 1083 05b5cc71ee4d2b4197774f5c7
5b5cc71ee4d2b4197774f5c7- 1[1, 32]false
- 2(0, 1)false
- 3[1, 1/2]true
- 4(1, 1/2]false
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Answer : 3. "[1, 1/2]"
Explanation :
Answer: C) [1, 1/2] Explanation: Probability of atleast one failure= 1 - no failure > 31/32= 1 - P5 > 31/32= P5<1/32= p < 1/2Also p > 0Hence p lies in [0,1/2].
Q: Why is burning coal a major source of pollution? 1083 05b5cc662e4d2b4197774be69
5b5cc662e4d2b4197774be69- Show Answer
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Answer :
Explanation :
Coal is chemically complex fuel. Whenever it is burned, gases are given off and particles of ash, called "fly ash," are released. Release of sulfur from burning into the air. The sulfur in coal combines with oxygen to form sulfur dioxide, which can be a major source of air pollution if emitted in large enough quantities. This stuff comes back as acid rain when it attaches itself to a raindrop. Today, many of the effects of coal burning have been reduced significantly or eliminated. This is super-nasty and is only stopped by buying low-sulfur coal from Montana or Wyoming. The eastern power plants have to pay to move the coal from out west and this increases the price of power production.
Q: First woman to win olympic medal for India 1081 05b5cc670e4d2b4197774c03e
5b5cc670e4d2b4197774c03e- 1Mary Komfalse
- 2Saina Nehwalfalse
- 3Karnam Malleshwaritrue
- 4P.V. Sindhufalse
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Answer : 3. "Karnam Malleshwari"
Explanation :
Answer: C) Karnam Malleshwari Explanation: The first Indian woman to ever win an Olympic medal for India was Karnam Malleswari who won a bronze medal at the Sydney Olympics 2000 in the Women's 69 kg category in Weightlifting. Karnam Malleswari is a retired Indian weightlifter. In 1995 she received the Rajiv Gandhi Khel Ratna, India's highest sporting honour, and in 1999 the civilian Padma Shri award. After that Indian women who won Olymic medals to India was : 1. Mary Kom at the London 2012 Summer Olympics won bronze medal in women's boxing. 2. Saina Nehwal was the first Indian to win a medal in Badminton at the Olympics, by winning the Bronze medal at the London Olympics 2012. 3. Sakshi Malik became the first Indian woman to win a medal in Wrestling. She won the Bronze medal in Women's 58 kg freestyle wrestling in 2016 Summer Olympics held in Rio. 4. P.V. Sindhu became the first ever Indian woman to win the Silver medal at the Olympics, by reaching the Badminton final at Rio Olympics 2016.
Q: If x and y are the two digits of the number 653xy such that this number is divisible by 80, then x+y is equal to ? 1081 05b5cc761e4d2b4197774fd62
5b5cc761e4d2b4197774fd62- 15false
- 24false
- 33false
- 42true
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Answer : 4. "2"
Explanation :
Answer: D) 2 Explanation: Since 653xy is divisible by 5 as well as 2, so y = 0.Now, 653x0 must be divisible by 8.So, 3x0 must be divisible by 8. This happens when x = 2x + y = (2 + 0) = 2.
Q: The wavelength of a wave is the distance between 1080 05b5cc6b0e4d2b4197774d283
5b5cc6b0e4d2b4197774d283- 1Crest and Troughfalse
- 2Crest and Crestfalse
- 3Trough and Troughfalse
- 4Both B & Ctrue
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Answer : 4. "Both B & C"
Explanation :
Answer: D) Both B & C Explanation: Distance between two Consecutive Crests or two Consecutive Troughs is called Wavelength. But the distance between crest and adjacent trough is half the wavelength. That is the distance between adjacent crest and trough is called Half the wavelength.
Q: What is the function of an antagonist in a story? 1078 05b5cc636e4d2b4197774ba33
5b5cc636e4d2b4197774ba33- Show Answer
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Answer :
Explanation :
The antagonist is the negative or opposing force in a story. It could be a human enemy, or it could be non-human, like an animal or something less tangible, like fear. The antagonist plays an important role in story development.
Q: 12 men complete a work in 9 days. After they have worked for 6 days, 4 more men join them. How many days will they take to complete the remaining work ? 1078 05b5cc6d7e4d2b4197774e700
5b5cc6d7e4d2b4197774e700- 12 daysfalse
- 22.5 daysfalse
- 32.25 daystrue
- 43 daysfalse
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Answer : 3. "2.25 days"
Explanation :
Answer: C) 2.25 days Explanation: 1 man's 1 day work = 1/108 12 men's 6 day's work = 1/9 x 6 = 2/3 Remaining work = 1 - 2/3 = 1/3 16 men's 1 day work = 1/108 x 16 = 4/274/27 work is done by them in 1 day. 1/3 work is done by them in 27/4 x 1/3 = 9/4 days.