If 8th term of an AP is 31 and 15th term is 16 more than the term 11th term find AP
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let a be the 1st term and d be the common difference
a8 = a + 7d = 31
a15 = a + 14d = a11 + 16
(a + 10d) + 16
a + 10d +16 = a + 14d
= a + 10d +16 = a + 10d + 4d
= 16 = 4d
d = 16/4 = 4
a + 7d = 31
a + 7(4) = 31
a + 28 = 31
a = 31 -28 = 3
a = 3 , d = 4 ...
therefore Ap = a , a+d , a+2d ,a+3d ......
= 3 , 3+4 ,3+2(4) , 3 + 3(4)
= 3 , 7 , 11 , 15 .......
a8 = a + 7d = 31
a15 = a + 14d = a11 + 16
(a + 10d) + 16
a + 10d +16 = a + 14d
= a + 10d +16 = a + 10d + 4d
= 16 = 4d
d = 16/4 = 4
a + 7d = 31
a + 7(4) = 31
a + 28 = 31
a = 31 -28 = 3
a = 3 , d = 4 ...
therefore Ap = a , a+d , a+2d ,a+3d ......
= 3 , 3+4 ,3+2(4) , 3 + 3(4)
= 3 , 7 , 11 , 15 .......
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