Q69 of 84 Page 5

The 9th term of an A.P. is equal to 6 times its second term. If its 5th term is 22, find the A.P. (CBSE 2013)

Given: a5 = 22

a + 4d=22 (i)


Acc. to question,


a9 = 6a2 (ii)


a9= a +8d


a2=a+d


Putting the value of a9 and a2 in (ii)


a +8d= 6(a +d)


2d=5a


2d=5(22 -4d)


22d=110


d=5


Now, putting the value of d in (i)


a=22 -4(5)=2


a1 = a=2


a2 =a +d=2 +5=7


a3 =a +2d=2 + 2(5)=12


Hence, the A.P. is

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