IIT JEE Practice Question and Answer
8Q: 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 ? 2579 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: Size of the primary memory of a pc ranges between 2578 05b5cc694e4d2b4197774c4a2
5b5cc694e4d2b4197774c4a2- 1256 kb to 640 kbtrue
- 264 kb to 256 kbfalse
- 3256 kb to 512 kbfalse
- 42 kb to 8 kbfalse
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Answer : 1. "256 kb to 640 kb"
Explanation :
Answer: A) 256 kb to 640 kb Explanation: Size of the primary memory of a PC ranges between 256 KB to 640 KB.
Q: The circumference of a circular base of Cylinder is 44 cm and its hight is 15 cm. Then the volume of the cylinder is? 2577 05b5cc6ade4d2b4197774d109
5b5cc6ade4d2b4197774d109- 12759 cub. cmfalse
- 22247 cub. cmfalse
- 32614 cub. cmfalse
- 42311 cub. cmtrue
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Answer : 4. "2311 cub. cm"
Explanation :
Answer: D) 2311 cub. cm Explanation: Given Circumference of a circular base of a cylinder = 44 cm We know that Circumference of a circle = 2πr = 44⇒r = 22π Now given the height of a cylinder h = 15 cm Volume of a cylinder V = πr2h = π22π215 = 22 x 22 x 153.14 = 2311 cm3.
Q: If two fractions, each of which has a value between 0 and 1, are multiplied together, the product will be : 2577 05b5cc6cfe4d2b4197774e303
5b5cc6cfe4d2b4197774e303- 1always greater than either of the original fractionsfalse
- 2always less than either of the original fractionstrue
- 3sometimes greater and sometimes less than either of the original fractionsfalse
- 4remains the samefalse
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Answer : 2. "always less than either of the original fractions"
Explanation :
Answer: B) always less than either of the original fractions Explanation: We can easily Answer this by taking some values. The question states that the two fractions, each have values between 0 and 1.Let us say one of the fraction is 1/2 and the other fraction is 1/3 .The product of the two fractions is 1/2 x 1/3 = 1/6 . is lesser than both 1/2 and 1/3 .So, the correct answer is that the product is always less than either of the original fractions.
Q: Most important weather phenomena occur in the 2577 05b5cc6a3e4d2b4197774cc2f
5b5cc6a3e4d2b4197774cc2f- 1Tropospherefalse
- 2Stratospherefalse
- 3Ionospherefalse
- 4Thermospheretrue
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Answer : 4. "Thermosphere"
Explanation :
Answer: D) Thermosphere Explanation: Most important weather phenomena occur in the layer of Thermosphere. Most of the weather phenomenon occur in the layer of Troposphere.
Q: Assertive sentences examples list. 2575 05b5cc604e4d2b4197774b4ec
5b5cc604e4d2b4197774b4ec- Show AnswerHide Answer
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Answer :
Explanation :
An assertive sentence is a sentence that state, assert, or declare something. It means it is a simple statement making thing. As it declares something, is also called as Declarative sentence. Examples of assertive sentence or statements :: 1. Anamika loves him very much. 2. He picks her daily. 3. Attitude is everything. 4. The sun sets in the west. 5. She likes roses. 6. He is a student. 7. Karthik planned a tour. 8. Peacock is a beautiful bird. 9. India is our country. 10. Joel want to be a doctor.
Q: The last two digits of 2151415? 2574 05b5cc6b9e4d2b4197774d6cb
5b5cc6b9e4d2b4197774d6cb- 181false
- 261false
- 391false
- 451true
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Answer : 4. "51"
Explanation :
Answer: D) 51 Explanation: Unit digit of this expression is always 1 as the base ends with 1. For the tenth place digit we need to multiply the digit in the tenth place of the base and unit digit of the power and take its unit digit. i.e, tenth place digit in 2151 is 5 and tenth place digit in power 415 is 1 And the units digit in the product of 5 x 1 = 5 Therefore, last two digits of 2151415 is 51.
Q: If a quarter kg of carrots costs 60 paise, how many paise will 200 gms cost ? 2573 05b5cc6d7e4d2b4197774e70a
5b5cc6d7e4d2b4197774e70a- 178 paisefalse
- 248 paisetrue
- 354 paisefalse
- 462 paisefalse
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Answer : 2. "48 paise"
Explanation :
Answer: B) 48 paise Explanation: Quarter of Kg means 250 gm Less weight, less price (Direct Proportion) So, 250 : 200 :: 60 : x => x = 48 So 200 gm will cost 48 paise.

