Number of 4 -digit numbers that are less than or equal to 2800 and either divisible by 3 or by 11 , is equal to

Number divisible by 3,1002,1005, ... , 2799 T_n=1002+3(n-1)=2799 => n=600 Number divisible by 11 are 164 Number divisible by 33 are 54 Total number =600+164-54=710

Number of 4 -digit numbers that are less than or equal ... | Sequence & Series (Mathematics)

Number divisible by $3,1002,1005, \ldots, 2799$ $\\T_n=1002+3(n-1)=2799 \Rightarrow n=600$ $\\$ Number divisible by 11 are 164 $\\$ Number divisible by 33 are 54 $\\$ Total number $=600+164-54=710$

Explanation

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