Respuesta :
10 years. Bill is 25, his sister is 5, and their mother is 60.
Sarah is twice as old as Bill so 2X=50 and X=25 so Bill is 25. Bill is 25 and bill is 5 times older than his sister Jane so 5n=25 N=5 so Jane is 5 years old. Jane's mom is 12 time older than Jane so 12x5=60 and so
60-50=10 so the answer is 10