-30/31*15/124+(-16/21)*(-7/8)
1) -30/31 : 15/124 = -30/31 * 124/15 = -2*4=-8
2) -16/21 * (-7/8) = 2/3
3) -8 + 2/3 = -7 3/3 + 2/3 = -7 1/3