If the sum of the series \( 20+19 \frac{3}{5}+19 \frac{1}{5}+18 \frac{4}{5}+\ldots . \). upto \( n \) terms is 488 and t…

If the sum of the series \( 20+19 \frac{3}{5}+19 \frac{1}{5}+18 \frac{4}{5}+\ldots . \). upto \( n \) terms is 488 and the \( n^{\text {th }} \) term is negative, then the value of \( n^{\text {th }} \) term is

[JEE Main 2020, 3 Sep (Shift 2)]