find the common difference of an A.P whose first term is 1/2 and the 8th term is 17/6. Also write its 4th term.
a = 1/2 , a8= 17/6 and let 'd ' be the common difference.
a8= 17/6 = a + (8-1)d
=> d = (17/6 -1/2)/7
=>d = 2
a4 = a + (4-1) d
=>a4 = 1/2 + 6 = 13/2.
Hope this helps out.