Question

10th term of an arithmetic sequence is 25 and 25 th term is 10.Then find the common difference​

Answer 1

$\huge\underline{\underline{\bf\bigstar ANSWER \bigstar }}$

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

Given ,

➤ 10th term = 25

➤ 25th term = 10

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           $\bf a_n = a+(n-1)d$

➥ 10th term = 25

➥ a + (10 - 1 )d = 25

➥ a + 9d = 25                ................... ( 1 )

➥ 25th term = 10

➥ a + (25 - 1)d = 10

➥ a + 24d = 10                 ................... (2)

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Eq(2) - Eq(1) ,

➡ 15d = - 15

➡ d = -1

Common Difference = -1

HOPE IT HELPS U ............ :)