Question

The 17th term of an A P exceeds its 10th term by 21 . Find the common difference

Answer 1

Let , a be the first term and d the common difference

$\to \bold{a_{17} - a_{10} = 7}</p><p> \\ \\ \to \bold{ (a + 16d) - (a + 9d) = 7 }\\ \\ </p><p> \to \bold{ 7d = 7 } \\ \\ \to \bold{ d = 1}</p><p>$

Thus , The common difference is 7