\[1)\ \frac{5! - 4!}{2!} = \frac{5 \bullet 4! - 4!}{2} = \frac{4 \bullet 4!}{2} =\]
\[= 2 \bullet 4! = 2 \bullet 4 \bullet 3 \bullet 2 = 48;\]
\[2)\ \frac{7! - 6!}{5!} = \frac{7 \bullet 6! - 6!}{5!} = \frac{6 \bullet 6!}{5!} =\]
\[= \frac{6 \bullet 6 \bullet 5!}{5!} = 6 \bullet 6 = 36;\]
\[3)\ \frac{54!}{53!} + \frac{70!}{69!} = \frac{54 \bullet 53!}{53!} + \frac{70 \bullet 69!}{69!} =\]
\[= 54 + 70 = 124;\]
\[4)\ \frac{60!}{58!} - \frac{50!}{48!} =\]
\[= \frac{60 \bullet 59 \bullet 58!}{58!} - \frac{50 \bullet 49 \bullet 48!}{48!} =\]
\[= 3540 - 2450 = 1090.\]