How many 2 - digit numbers are divisible by 3?

1.	How many 2 - digit numbers are divisible by 3?
Answer» To Find: 2 - digit numbers divisible by 3. First 2 - digit number divisible by 3 is 12 Second 2 - digit number divisible by 3 is 15 and Last 2 - digit number divisible by is 99. Given: The AP is 12, 15, 18,…………..,99 a₁ = 12, a₂ = 15, d = 15 –12 = 3 and a_n = 99 (Where a = a₁ is First term, a₂ is Second term, a_n is n^th term and d is common difference of given AP) Formula Used: a_n = a + (n – 1)d 99 = 12 + (n - 1)3 87 = (n – 1)3 29 = (n – 1) n = 30 So, There are total of 30 two - digit number which is divisible by 3.

Answer»

To Find: 2 - digit numbers divisible by 3.

First 2 - digit number divisible by 3 is 12

Second 2 - digit number divisible by 3 is 15 and

Last 2 - digit number divisible by is 99.

Given: The AP is 12, 15, 18,…………..,99

a₁ = 12, a₂ = 15, d = 15 –12 = 3 and a_n = 99

(Where a = a₁ is First term, a₂ is Second term, a_n is n^th term and d is common difference of given AP)

Formula Used: a_n = a + (n – 1)d

99 = 12 + (n - 1)3

87 = (n – 1)3

29 = (n – 1)

n = 30

So, There are total of 30 two - digit number which is divisible by 3.

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