Question

how many two digit numbers sre divisible by 7​

Answer 1

Answer:

we use ap to determine the answer

Thus, we have to determine the number of terms in the sequence.

14, 21, 28,..., 98

Clearly, it is an A.P. with first term =14 and common difference =7 i.e. a =14 and d =7.

Let this $n th$ be the

 term in this A.P.  

Then, $n th$  term =98

⟹14+(n−1)×=98

⟹14+7n−7=98

⟹7n=91⟹n=13

Hence, there are 13 numbers of two digits which are divisible by 7.