Sam weighs 35 kg.<br>
Tom weighs 8 kg more than Sam, so Tom = 35 + 8 = 43 kg.<br>
Tom weighs 11 kg less than Fred, so Fred weighs 11 kg more than Tom.<br><br>
&bull; Fred = Tom + 11 = 43 + 11 = 54<br>
<br>
Fred weighs 54 kg.<br>
Check: Sam 35, Tom 35+8=43, Fred 43+11=54. ✓