IIT JEE Practice Question and Answer
8Q: Three taps P, Q and R can fill a tank in 12 hrs, 15 hrs and 20 hrs respectively. If P is open all the time and Q and R are open for one hour each alternately, starting with Q, then the tank will be full in how many hours ? 2740 05b5cc6c0e4d2b4197774dafb
5b5cc6c0e4d2b4197774dafb- 19 hrsfalse
- 27 hrstrue
- 313 hrsfalse
- 411 hrsfalse
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Answer : 2. "7 hrs"
Explanation :
Answer: B) 7 hrs Explanation: Given, P can fill in 12 hrs Q can fill in 15 hrs R can fill in 20 hrs => Volume of tank = LCM of 12, 15, 20 = 60 lit => P alone can fill the tank in 60/12 = 5 hrs => Q alone can fill the tank in 60/15 = 4 hrs => R alone can fill the tank in 60/20 = 3 hrs Tank can be filled in the way that (P+Q) + (P+R) + (P+Q) + (P+R) + .... => Tank filled in 2 hrs = (5+4) + (5+3) = 9 + 8 = 17 lit => In 6 hrs = 17 x 6/2 = 51 lit => In 7th hr = 51 + (5+4) = 51 + 9 = 60 lit => So, total tank will be filled in 7 hrs.
Q: The accounting software Tally was developed by 2737 05b5cc68ee4d2b4197774c401
5b5cc68ee4d2b4197774c401- 1Wiprofalse
- 2TCStrue
- 3HCLfalse
- 4Infosysfalse
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Answer : 2. "TCS"
Explanation :
Answer: B) TCS Explanation: Tally is one of the best business accounting software for accounting, inventory, payroll. It is economical and one of the most popular ERP software solutions available in the industry. Tally, an accounting software was developed by the multinational company TCS - Tata Consultancy Services.
Q: If (1 × 2 × 3 × 4 ........ × n) = n!, then 15! - 14! - 13! is equal to ___? 2725 05b5cc6bee4d2b4197774d997
5b5cc6bee4d2b4197774d997- 114 × 13 × 13!false
- 215 × 14 × 14!false
- 314 × 12 × 12!false
- 415 × 13 × 13!true
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Answer : 4. "15 × 13 × 13!"
Explanation :
Answer: D) 15 × 13 × 13! Explanation: 15! - 14! - 13! = (15 × 14 × 13!) - (14 × 13!) - (13!) = 13! (15 × 14 - 14 - 1) = 13! (15 × 14 - 15) = 13! x 15 (14 - 1) = 15 × 13 × 13!
Q: The ages of Anushka, Kajal and Charu latha together are 57 years. Bharti is thrice as old as Anushka and Charu latha is 12 years older than Anushka. Then, the respective age of Anushka, Kajal and Charu latha is ? 2725 05b5cc741e4d2b4197774f9b8
5b5cc741e4d2b4197774f9b8- 127, 9, 21false
- 29, 21, 27false
- 321, 27, 9false
- 49, 27, 21true
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Answer : 4. "9, 27, 21"
Explanation :
Answer: D) 9, 27, 21 Explanation: Let Anushka age = XCharu latha 12 yrs older than Anushka so Charu latha age = x+12Kajal is thrice as old as Anushka so Kajal age = 3xThe ages of Anushka, Kajal and Charu latha together are 57 yearsi.e x + (x+12) + 3x = 57=> 5x = 45:- x = 9Anushka age = 9Kajal age = 3x = 27Charu latha age = x+12 = 21
Q: कौन सा तत्व मैग्नीशियम की तरह सबसे अधिक व्यवहार करता है? 2724 05b5cc60ae4d2b4197774b568
5b5cc60ae4d2b4197774b568- 1सिलिकॉनfalse
- 2स्ट्रोंटियमtrue
- 3सल्फरfalse
- 4टिनfalse
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Answer : 2. "स्ट्रोंटियम"
Explanation :
Answer: B) स्ट्रोंटियम व्याख्या: हम जानते हैं कि आवर्त सारणी के एक ही समूह के तत्वों में समान विशेषताएं होती हैं। यहाँ मैग्नीशियम और स्ट्रोंटियम ने कुछ समान गुण साझा किए क्योंकि वे दोनों एक ही समूह के हैं। Sr स्ट्रोंटियम का रासायनिक प्रतीक है जो एक समूह दो तत्व है; इसका परमाणु क्रमांक 38 है।
Q: A rectangular block has the dimensions 5x6x7 cm it is dropped into a cylindrical vessel of radius 6cm and height 10 cm. If the level of the fluid in the cylinder rises by 4 cm, What portion of the block is immersed in the fluid ? 2720 05b5cc70ee4d2b4197774f337
5b5cc70ee4d2b4197774f337- 122/7 x 24/35true
- 222/7 x 36 x 4false
- 322/7 x 36/5false
- 422/7 x 37/21false
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Answer : 1. "22/7 x 24/35"
Explanation :
Answer: A) 22/7 x 24/35 Explanation: Since level of water increased in cylinder by height 4. This is because of the rectangular block . Therefore , area of rectangular block immersed in water is = 227×6×6×4 Thats why portion of block immersed in water is = (22/7 * 36 * 4) / total vol. of rectangle = (22/7 * 36 * 4)/ (7*5*6) = (22/7 * 24)/ 35.
Q: If 15 men 4 hours per day works for 14 days get Rs.35/- then how many men required if the work is 8 hours per day for 10 days they get 50/- ? 2719 05b5cc754e4d2b4197774fb68
5b5cc754e4d2b4197774fb68- 112false
- 213false
- 314false
- 415true
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Answer : 4. "15"
Explanation :
Answer: D) 15 Explanation: We know M1×D1×H1W1 = M2×D2×H2W2 => 15×4×1435 = M×8×1050 => M = 15
Q: How many parallelograms will be formed if 7 parallel horizontal lines intersect 6 parallel vertical lines? 2718 05b5cc754e4d2b4197774fbb4
5b5cc754e4d2b4197774fbb4- 1215false
- 2315true
- 3415false
- 4115false
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Answer : 2. "315"
Explanation :
Answer: B) 315 Explanation: Parallelograms are formed when any two pairs of parallel lines (where each pair is not parallel to the other pair) intersect. Hence, the given problem can be considered as selecting pairs of lines from the given 2 sets of parallel lines. Therefore, the total number of parallelograms formed = 7C2 x 6C2 = 315