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  1. The sum of all the 3-digit numbers is
    1. 98901
    2. 494550
    3. 8991
    4. 899
Correct Option: B

First 3 – digit number = 100
Last 3 – digit number = 999
Number of terms = 900

∴  S =
n
(a + 1)
2

=
900
[100 + 999]
2

= 450 × 1099 = 494550


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