topgre wrote:
Choice (2)
The question is actually an arithmetic progression question
The sum of 'n' terms of an AP can be found using the formula n/2(a + l), where a is the first term and l is the last term of the sequence.
In this case, the first 2 digit number that will give a remainder of 3 when divided by 7 is 10
The last number in the series is 94.
'n' can be found by substituting the values of a, l and d (7 is the common difference in this case) in the following formula
l = a + (n - 1)d
94 = 10 + (n - 1)* 7
hence, n = 13.
Sum of the series will therefore be 13/2 (10 + 94) = 13 * 52 = 676.
Choice (2) is correct
Thanks for your clear explanation.
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