Question

The sum of 6th and 10th terms of ap is 92 and the sum of 8th and 13th terms is 112. find ap

Answer 1

a+ 5d + a + 9d = 92 
2a + 14d = 92 
a + 7d = 46 
a = 46 - 7d--------(1) 
=> a + 7d + a + 12d = 112 
2a + 19d = 112 
, 2 (46 - 7d) + 19d = 112-(using (1)) 
92 - 14d + 19d = 112 
d = 4 
a = 18 
A.P. = 18, 22 , 26.....