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OverviewExercise"Do not wait for leaders; do it alone, person to person."
- Mother Teresa
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| 91. |
Which one of the following is a prime number ?
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Answer: Option C
Explanation:
437 > 22
All prime numbers less than 22 are : 2, 3, 5, 7, 11, 13, 17, 19.
161 is divisible by 7, and 221 is divisible by 13.
373 is not divisible by any of the above prime numbers.
 373 is prime.
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| 92. |
The smallest 6 digit number exactly divisible by 111 is:
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| A. |
111111 | B. |
110011 | | C. |
100011 | D. |
110101 | | E. |
None of these |
Answer: Option E
Explanation:
The smallest 6-digit number 100000.
111) 100000 (900
999
-----
100
---
Required number = 100000 + (111 - 100)
= 100011.
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| 93. |
The largest 5 digit number exactly divisible by 91 is:
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Answer: Option B
Explanation:
Largest 5-digit number = 99999
91) 99999 (1098
91
---
899
819
----
809
728
---
81
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Required number = (99999 - 81)
= 99918.
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| 94. |
| 768 x 768 x 768 + 232 x 232 x 232 |
= ? |
| 768 x 768 - 768 x 232 + 232 x 232 |
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Answer: Option A
Explanation:
| Given Exp. = |
(a3 + b3) |
= (a + b) = (768 + 232) = 1000 |
| (a2 - ab + b2) |
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| 95. |
The smallest 5 digit number exactly divisible by 41 is:
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Answer: Option E
Explanation:
The smallest 5-digit number = 10000.
41) 10000 (243
82
---
180
164
----
160
123
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37
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Required number = 10000 + (41 - 37)
= 10004.
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| 96. |
How many terms are there in the G.P. 3, 6, 12, 24, ... , 384 ?
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Answer: Option C
Explanation:
| Here a = 3 and r = |
6 |
= 2. Let the number of terms be n. |
| 3 |
Then, tn = 384  arn-1 = 384
3 x 2n - 1 = 384
2n-1 = 128 = 27
n - 1 = 7
n = 8
Number of terms = 8.
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| 97. |
If x and y are positive integers such that (3x + 7y) is a multiple of 11, then which of the following will be divisible by 11 ?
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| A. |
4x + 6y
| B. |
x + y + 4
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9x + 4y
| D. |
4x - 9y
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Answer: Option E
Explanation:
By hit and trial, we put x = 5 and y = 1 so that (3x + 7y) = (3 x 5 + 7 x 1) = 22, which is divisible by 11.
(4x + 6y) = ( 4 x 5 + 6 x 1) = 26, which is not divisible by 11;
(x + y + 4 ) = (5 + 1 + 4) = 10, which is not divisible by 11;
(9x + 4y) = (9 x 5 + 4 x 1) = 49, which is not divisible by 11;
(4x - 9y) = (4 x 5 - 9 x 1) = 11, which is divisible by 11.
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| 98. |
9548 + 7314 = 8362 + (?)
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Answer: Option A
Explanation:
9548 16862 = 8362 + x
+ 7314 x = 16862 - 8362
----- = 8500
16862
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| 99. |
In a division sum, the remainder is 0. As student mistook the divisor by 12 instead of 21 and obtained 35 as quotient. What is the correct quotient ?
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Answer: Option C
Explanation:
Number = (12 x 35)
Correct Quotient = 420 ÷ 21 = 20
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| 100. |
2 + 22 + 23 + ... + 29 = ?
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Answer: Option E
Explanation:
| This is a G.P. in which a = 2, r = |
22 |
= 2 and n = 9. |
| 2 |
| Sn = |
a(rn - 1) |
= |
2 x (29 - 1) |
= 2 x (512 - 1) = 2 x 511 = 1022. |
| (r - 1) |
(2 - 1) |
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