How many three digit number are divisible by 7?

1.	How many three digit number are divisible by 7?
Answer» The first 3-digit number which is divisible by 7 is 105The last 3-digit number which is divisible by 7 is 994The list of 3-digit numbers divisible by 7 are105, 112, 119,…..994 which forms an A.PConsider a formulaT(n) = a + (n – 1)dWherea = 105d = 7T(n) = 994994 = 105 + (n – 1)7889 = 7n – 77n = 896n = 128∴ There are 128 3-digits number which are divisible by 7. AP 105,112........994A=105 d=7 an=994n=? An= a+(n-1) DN=128There are 128 no.

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