At a meeting of musicians, 56 of the musicians play the piano but only 35 play the violin. What is the minimum number of people at the meeting who play both piano and violin?

Ametal rod needs to be 9 feet and 5.5 inches in length. the sections of the poles being used are each 1 foot and 10.5 inches long. how many 1ft 10.5in sections would be needed to complete the 9ft 5.5in metal rod? and how many inches of material will be left?