Odpowiedź:
a) 4/21 * (-7/6) * (-9/2)= 2/3 * (-1/2) * ( -3/1) = 1/1 * (-1/1) = 1/1= 1
b) 2/3 * (-6/7) * 7/8= 1/1 * 9-2/10 * 1/4 = (-1/1) * 1/2= -1/2
c) -3/20 * 10/9 * 4/11 = -1/2 * 1/3 * 4/11= -1/1 * 1/1 * 2/11= -2/33
d) 8/3* 15/14 * 7/12= 2/1 * 5/2 * 1/3= 5/3= 1 i 2/3
e) nie mam
f) 5/8 * 18/35 * (-4/27)= 1/2 * 2/7 * (-1/3)= 1/21
liczę że pomogłam :>
