Q5 of 52 Page 1

The 7th term of an A.P. is 20 and its 13th term is 32 Find the A.P.

Given,


The 7th term of AP = 20


13th term of AP = 32


Let the first term of AP = a


And the difference of AP = d


So, we have;


a + 6d = 20………… (i)


a + 12d = 32 ………..(ii)


Now,


Subtracting the (i) equation from (ii) equation,


We get;



d = 12/6 = 2


d = 2


By putting the value of ‘d’ in equation (i),


a + 6 (2) = 20
a + 12 = 20
a = 20 - 12
a = 8,


d = 2
So, the required A.P is 8, 10, 12, 14, 16, 18.......


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