Question

which term of the AP 20, 19 1/4, 18 1/2, 17 3/4.... is it's first negative Term?

Answer 1

20,77/4,37,/2,71/4
a=20
d=a2-a1
=77/4 - 20
=77 - 80/4
=-3/4
0>20+(n-1) -3/4
0>20-3n/4 + 3/4
0>20/1 + 3/4 - 3n/4
0>80+3/4 - 3n/4
0>83/4 - 3n/4
3n/4 = 83/4
3n=83
n=27.6666666667
Hence, the required term is 28th term