Four singers take part in a musical round of 4 equal lines, each finishing after singing the round through three times.
The second singer begins when the first singer begins the second line,the third singer begins when the first singer begins the third line,the fourth singer begins when the first singer begins the fourth line.

Find the fraction of the total singing time that all four are singing at the same time.

Charlie's first solution is correct if each singer sings the round only once.

Posted by Steve Herman on 2018-03-26 11:44:46