5.542 Выполните действия: а) 3/8 : 3/4 * 2/3; б) 10/7 * 3/4 : 5/14.

a) 3/8 * 4/3 * 2/3 = (3*4*2)/(8*3*3) = 24/72 = 1/3.
б) 10/7 * 3/4 * 14/5 = (10*3*14)/(7*4*5) = 420/140 = 3.