Aloha :)
Willkommen in der Mathelounge... \o/
$$76_{10}=4\cdot16+12=4C_{16}={\overbrace{0100}^{=4_{10}}\,\overbrace{1100}^{=12_{10}}}$$$$76_{16}={\overbrace{0111}^{=7_{10}}\,\overbrace{0110}^{=6_{10}}}_2$$$${\overbrace{1101}^{=13_{10}}\,\overbrace{1101}^{=13_{10}}}_2=DD_{16}=13\cdot16+13=221_{10}$$$$1101\,1101_2=DD_{16}$$