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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. Five coins are tossed at a time. Then, the probability of obtaining at least one tail is
Options- A. 31/32
- B. 1/32
- C. 1/5
- D. 5/32 Discuss
- 2. Find the maximum number of tree which can plant 20 m apart on the two side of straight road 1760 m long
Options- A. 174
- B. 176
- C. 180
- D. 178 Discuss
- 3. 1307 x 1307 =?
Options- A. 1601249
- B. 1607249
- C. 1701249
- D. 1708249 Discuss
- 4. The circumferences of two concentric are 176 m and 132 m respectively. what is the difference between their radii?
Options- A. 5 meter
- B. 7 meter
- C. 8 meter
- D. 44 meter Discuss
- 5. (1/2 ÷ 4 + 20) / (1/2 x 4 + 20) =?
Options- A. 81 / 88
- B. 23/11
- C. 161 / 176
- D. 1 Discuss
- 6. Find the cardinal number of the following set {x: x = 2n, n ? N, 4 ? x ? 11}
Options- A. 8
- B. 6
- C. 12
- D. 4 Discuss
- 7. If a fraction is multiplied by itself and then divided by the reciprocal of the same fraction, the result is 18 26/ 27. Find the fraction.
Options- A. 8/27
- B. 11/3
- C. 22/3
- D. 32/3 Discuss
- 8. (0.04) 3 =?
Options- A. 0.064
- B. 0.0064
- C. 0.00064
- D. 0.000064 Discuss
- 9. If a + b + c = 8, then the value of (a ? 4)3 + (b ? 3)3 + (c ? 1)3 ? 3 (a ? 4) (b ? 3) (c ? 1) is
Options- A. 2
- B. 4
- C. 1
- D. 0 Discuss
- 10. 3571 +? - 6086 = 155
Options- A. 2400
- B. 2630
- C. 2515
- D. None of these Discuss
More questions
Correct Answer: 31/32
Explanation:
Total events = n (s) = 25 = 32
n(E) of getting heads = 1
p(E) = 1/32
? n(E) = 1 - p(E) = 1 - 1/32 = 31/32
Correct Answer: 178
Explanation:
Number of trees that can be planted on one side of road = (1760 / 20) + 1
= 88 + 1
=89
? Trees on the both side = 2 x 89=178
Correct Answer: 1708249
Explanation:
1307 x 1307 = (1307)2
= (1300 + 7 )2
= (1300)2 + (7)2 + 2 x 1300 x 7
= 1690000 + 49 +18200
= 1708249
Correct Answer: 7 meter
Explanation:
? 2?R - 2?r = (176-132)
? 2?(R-r) = 44
? R-r = ( 44 x 7 )/ (2 x 22)
= 7 m
Correct Answer: 161 / 176
Explanation:
Given Exp. = (1/2 x 1/4 + 20) / (2 + 20) = (161/8) x (1/22)
= 161 / 176
Correct Answer: 4
Explanation:
NA
Correct Answer: 22/3
Explanation:
If the required fraction be P
According to the question
(P x P) / (1/P) = 1826/27
? P3 = 512/27
? P = 8/3 = 22/3
Correct Answer: 0.000064
Explanation:
(0.04)3 = 0.04 x 0.04 x 0.04
= 0.000064
Correct Answer: 0
Explanation:
We have p3 + q3 + r3 ? 3pqr = (p + q + r) (p2 + q2 + r2 ?pq ? qr - rp)
Here p = a ? 4, q = b ? 3, r = c ?1
So, given expression is (p + q + r) (p2 + q2 + r2 ? pq ? qr ? rp)
= (a ? 4 + b ? 3 + c ? 1) (p2 + q2 + r2 ? pq ? qr ? rp)
= (a + b + c ? 8) (p2 + q2 + r2 ? pq ? qr ? rp)
= (8 ? 8) (p2 + q2 + r2 ? pq ? qr ? rp)
? (a ? 4)3 + (b ? 3)3 + (c ? 1)3 ? 3 (a ? 4) (b ? 3) (c ? 1) = 0
Correct Answer: 2630
Explanation:
Let 3571 + x - 6086 = 115
Then, x = 6086 +115 -3571
= 6201-3571
= 2630
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