Question

Find the 25th term of the AP `-5, (-5)/(2), 0, (5)/(2),….`

Answer 1

The given AP is `-5, (-5)/(2), 0, (5)/(2), ….`
Its first term = -5 and common difference `= ((5)/(2) - 0) = (5)/(2)`.
` therefore` a= -5 and d = `(5)/(2)`.
`rArr T_(25) = a + (25-1) d`
` =a +24d = (-5) + (24 xx (5)/(2)) = -5 + 60 = 55.`
Hence, 25th term = 55.