Answer:
[tex] \frac{15}{s + 8} = \frac{12}{16} \div \frac{4}{4} \: or \: \frac{3}{4} [/tex]
[tex] \frac{15}{s + 8} = \frac{3}{4} \\ 4 \times 15 = 3 \times (s + 8) \\ 60 = 3s + 24 \\ 60 - 24 = 3s + 24 - 24 \\ 36 = 3s[/tex]
[tex] \frac{36}{3} = \frac{3s}{3} \\ s = 12[/tex]
