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- Question
- A library has 'a' copies of one book, 'b' copies of each of two book, 'c' copies of each of three books and single copy of 'd' book. The number of ways in which these books can be distribute is?
Options- A. (a + b + c + d)! / (a! b! c!)
- B. (a + 2b + 3c + d)! / {a! (b!)2 (c!)3}
- C. (a + 2b + 3c + d )! / (a! b! c!)
- D. None of these
- Correct Answer
- (a + 2b + 3c + d)! / {a! (b!)2 (c!)3}
ExplanationTotal number of books = a + 2b + 3c + d . Since there are 'b' copies of each of two books, 'c' copies of each of three books and single copy of 'd' book.
Therefore, the total number of arrangements is = (a + 2b + 3c + d )! / {a! (b!)2 (c!)3} - 1. In, ?ABC, D and E are the mid-points of AB and AC respectively. Find the ratio of the areas of ?ADE and ?ABC.
Options- A. 1 2
- B. 1 4
- C. 3 4
- D. 1 8 Discuss
- 2. 22020 ÷ 0.011=?
Options- A. 20020
- B. 2000000
- C. 200200
- D. 200002 Discuss
- 3. How many times are the hands of a clock is at right angle in a day?
Options- A. 22
- B. 24
- C. 44
- D. 48 Discuss
- 4. The unit digit in the product (784 x 618 x 917 x 463) is:
Options- A. 2
- B. 3
- C. 4
- D. 5 Discuss
- 5. If the true discount on s sum due 2 years hence at 14% per annum be Rs. 168, the sum due is:
Options- A. Rs. 768
- B. Rs. 968
- C. Rs. 1960
- D. Rs. 2400 Discuss
- 6. ?. 8x 2 + 6x = 5
?. 12y 2 ? 22y + 8 = 0
Options- A. 1
- B. 2
- C. 3
- D. 4 Discuss
- 7. 15, 31, 63, 127, 255, (...)?
Options- A. 513
- B. 511
- C. 517
- D. 523 Discuss
- 8. Find the probability that a vowel selected at random from the 5 vowels is an 'i'.?
Options- A. 4/5
- B. 1/3
- C. 1/5
- D. 1/2 Discuss
- 9. 396, 462, 572, 427, 671, 264
Options- A. 396
- B. 427
- C. 671
- D. 264 Discuss
- 10. If 90% of A = 30% of B and B = C% of A,then the value of C is?
Options- A. 900
- B. 800
- C. 600
- D. 300 Discuss
More questions
Correct Answer: 1 4
Explanation:
Correct Answer: 2000000
Explanation:
22020 ÷ 0.011 = 2001818.181 ? 2000000
Correct Answer: 44
Explanation:
In 12 h, they are at a right angles, 22 times.
So, in 24 h, they are at right angles, 44 times.
Correct Answer: 2
Explanation:
Unit digit in the given product = Unit digit in (4 x 8 x 7 x 3) = (672) = 2
Correct Answer: Rs. 768
Explanation:
| P.W. = | 100 x T.D. | = | 100 x 168 | = 600. |
| R x T | 14 x 2 |
∴ Sum = (P.W. + T.D.) = Rs. (600 + 168) = Rs. 768.
Correct Answer: 3
Explanation:
Correct Answer: 511
Explanation:
Each number is double the preceding one plus 1. So, the next number is (255 x 2) + 1 = 511.
Correct Answer: 1/5
Explanation:
Here, n(5) = {a, e, i,o, u}
and E = Event of selecting the vowel i = {i}
? P(E)= n(E)/n(S) = 1/5
Correct Answer: 427
Explanation:
Correct Answer: 300
Explanation:
? 90A/100 = 30B/100 = (30/100) x AC/100
? C = 100 x (100/30) x (90/100) = 300
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