3/5: (7/60):(-3 11/15) * 1 2/3=
= 3/5 * 60/7 : (- 56/15) * 5/3 = 36/7 * (-15/56) *5/3 =
= - (36*15*5) /(7*56*3) = -9*25/7*14=-225/98 = - 2 29/98
2) 2 2/7 * 3 8/15 + 1 7/15* 2 2/7 - 72/7*5 =
= 2 2/7( 3 8/15 + 1 7/15) - 72/7*5=
=14/7 *5 - 72/7 *5 = 5/7 (14-72) = 5/7*(-58) = -290/7 = -41 3/7