Simplify the following expression.

y26y+8y213y+30y220y+100y212y+20\displaystyle \frac{{{y}^{{2}}-{6}{y}+{8}}}{{{y}^{{2}}-{13}{y}+{30}}}\cdot\frac{{{y}^{{2}}-{20}{y}+{100}}}{{{y}^{{2}}-{12}{y}+{20}}}