Find the 31st term of an AP whose 11th term is 38 and the 16th term is

1.	Find the 31st term of an AP whose 11th term is 38 and the 16th term is 73
Answer» a11\xa0= a+(n-1)d38= a+(11-1)d38=a+10d ...(1)a16\xa0= a+(n-1)d73 = a+(16-1)d73= a+15d ....(2)Subtracting (1) from (2), we get5d= 35d= 35/5 = 7substituting value of d in (1), we get38= a+ 10738= a+70a= 38-70a= -32So 31 st term a31\xa0= a+(n-1)da31\xa0= -32+(31-1)7a31\xa0= -32+30*7a31\xa0= -32+210a31 = 178\xa0

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