Total member enrolled in gymnasium B in 1993 and 1994 together is what % more than members enrolled in gymnasium A in 1990 and 1994 together?

Required % = $frac{{left( {240 + 150} ight) - left( {170 + 70} ight)}}{{left( {170 + 70} ight)}} imes 100$

$= frac{{150}}{{240}} imes 100 = 62.5{ m{\% }}$