Numbers-Data Intensity 1 Multiple Questions and Answers.
Exercise Questions ::
Numbers
| Answer: Option C |
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Sum of digits = (5 + 1 + 7 + x + 3 + 2 + 4) = (22 + x), which must be divisible by 3.
∴ x = 2. |
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Published by:Michael Daani
| Answer: Option A |
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| Explanation: |
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The smallest 3-digit number is 100, which is divisible by 2.
100 is not a prime number.
101 < 11 and 101 is not divisible by any of the prime numbers 2, 3, 5, 7, 11.
101 is a prime number.
Hence 101 is the smallest 3-digit prime number. |
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Published by:Michael Daani
| Answer: Option D |
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| Explanation: |
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(4 + 5 + 2) - (1 + 6 + 3) = 1, not divisible by 11.
(2 + 6 + 4) - (4 + 5 + 2) = 1, not divisible by 11.
(4 + 6 + 1) - (2 + 5 + 3) = 1, not divisible by 11.
(4 + 6 + 1) - (2 + 5 + 4) = 0, So, 415624 is divisible by 11. |
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Published by:Michael Daani
| Answer: Option A |
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| Explanation: |
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19657 Let x - 53651 = 9999
33994 Then, x = 9999 + 53651 = 63650
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53651
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Published by:Michael Daani
| Answer: Option A |
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| Explanation: |
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Let Sn =(1 + 2 + 3 + ... + 45). This is an A.P. in which a =1, d =1, n = 45.
Sn = |
n |
[2a + (n - 1)d] |
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45 |
x [2 x 1 + (45 - 1) x 1] |
= |
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45 |
x 46 |
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= (45 x 23) |
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= 45 x (20 + 3)
= 45 x 20 + 45 x 3
= 900 + 135
= 1035.
Short way:
Sn = |
n(n + 1) |
= |
45(45 + 1) |
= 1035. |
2 |
2 |
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Tutorial Link: |
Published by:Michael Daani
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