IIT JEE Practice Question and Answer
8Q: The product of a number and its multiplicative inverse is 3964 05b5cc64de4d2b4197774bc70
5b5cc64de4d2b4197774bc70- 11true
- 20false
- 3-1false
- 4Infinityfalse
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Answer : 1. "1"
Explanation :
Answer: A) 1 Explanation: The mutiplicative inverse of a number is nothing but a reciprocal of a number. Now, the product of a number and its multiplicative inverse is always equal to 1. For example : Let the number be 15 Multiplicative inverse of 15 = 1/15 The product of a number and its multiplicative inverse is = 15 x 1/15 = 1.
Q: Soil erosion on hillslopes can be checked by 3961 05b5cc67ee4d2b4197774c26a
5b5cc67ee4d2b4197774c26a- 1Terrace cultivationtrue
- 2Contour ploughingfalse
- 3Afforestationfalse
- 4Strip croppingfalse
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Answer : 1. "Terrace cultivation"
Explanation :
Answer: A) Terrace cultivation Explanation: Hence, soil erosion on hillslopes can be checked by Terrace cultivation.
Q: The present average age of a family of five members is 26 years. If the present age of the youngest member in the family is ten years, then what was the average age of the family at the time of the birth of the youngest member ? (Assume no death occurred in the family since the birth of the youngest) 3951 05b5cc6e7e4d2b4197774ed8d
5b5cc6e7e4d2b4197774ed8d- 119 yearsfalse
- 216 yearsfalse
- 318 yearsfalse
- 420 yearstrue
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Answer : 4. "20 years"
Explanation :
Answer: D) 20 years Explanation: Present total age of the members = 26(5) = 130 years. Present age of the youngest member = 10 years Present total age of the remaining four members = 130 -10 = 120 years Their average age at the time of the birth of the youngest member = 120-4×104 = 30 - 10 = 20 years.
Q: In a mens hostel, there were 95 students. To accommodate 30 more students the average is decreased by rupees 5. But total expenditure increased by Rs.500. Find the total expenditure of the hostel now ? 3936 05b5cc6d4e4d2b4197774e5cf
5b5cc6d4e4d2b4197774e5cf- 1Rs. 4680true
- 2Rs. 4420false
- 3Rs. 4960false
- 4Rs. 5480false
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Answer : 1. "Rs. 4680"
Explanation :
Answer: A) Rs. 4680 Explanation: Let the expenditure on the 95 students be 'x' Then, 95x + 500 = 120(x – 5)95x + 500 = 120x - 600120x - 95x = 110025x = 1100=> x = 44 Therefore, total expenditure of the hostel becomes95 x 44 + 500 = 4680.
Q: Missing Slot Covers on a Computer can cause 3923 15b5cc6ade4d2b4197774d118
5b5cc6ade4d2b4197774d118- 1Power Surgesfalse
- 2Incomplete Path of ESDfalse
- 3Over Haeattrue
- 4EMIfalse
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Answer : 3. "Over Haeat"
Explanation :
Answer: C) Over Haeat Explanation: The slot covers on a computer reduce the dust build up inside the computer. So the slot covers should be present in proper place.The missing covers can disrupt the airflow design of the case and cause overheating problems.
Q: In an objective competitive exam, a correct answer score 4 marks and on a wrong answer 2 marks are negatively added. A student scores 420 marks from 150 question. How many answers were correct ? 3897 05b5cc74fe4d2b4197774fb4e
5b5cc74fe4d2b4197774fb4e- 1145false
- 2138false
- 3125false
- 4120true
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Answer : 4. "120"
Explanation :
Answer: D) 120 Explanation: let x be the correct answer and y be the wrong answerso the total number of questions is (x + y) = 150.....(1)=> 4x - 2y = 420.....(2)By solving (1) & (2), we get => 6x = 720hence x = 120Therefore, number of correct answers are 120.
Q: By selling an article at Rs.800, a shopkeeper makes a profit of 25%.At what price should he sell the article so as to make a loss of 25%? 3881 05b5cc7bbe4d2b419777509d2
5b5cc7bbe4d2b419777509d2- 1Rs.720false
- 2Rs.640false
- 3Rs.540false
- 4Rs.480true
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Answer : 4. "Rs.480"
Explanation :
Answer: D) Rs.480 Explanation: SP = Rs.800 ; Profit = 25% CP = SP x 100100+P% = 800 x 100100+25 = 640 Now, CP = Rs.640 Loss = 25% = 25% of Rs.640 = Rs.160 Thus, SP = CP - Loss = Rs.640 - Rs.160 = Rs.480
Q: Which of the following contributed to the failure of prohibition? 3875 05b5cc69de4d2b4197774c8a2
5b5cc69de4d2b4197774c8a2- 1it was not imposed strictly on immigrantsfalse
- 2many americans didnt consider drinking to be a crimefalse
- 3it adversely affected american productivityfalse
- 4organized crime controlled illegal alcohol productiontrue
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Answer : 4. "organized crime controlled illegal alcohol production"
Explanation :
Answer: D) organized crime controlled illegal alcohol production Explanation: Crime connected with illegal alcohol production and sale became a major issue so that even many people who had originally supported Prohibition decided that it needed to be repealed.