1. a)4 1/6*2 2/5= 25/6*12/5=300/30=10
b)2 1/10*2 1/7= 21/10*15/7=3/2*3/1=4.5
v)1 7/8*2 2/5= 15/8*12/5=3/2*3/1=4.5
g) 2 2/21*3 1/2=44/21*7/2=22/3*1/1=22/3=71/3
2. 6.2/5*2.1/4*1.7/8=32/5*9/4*15/8=4/1*9/4*3/1=1/1*9/1*3/1=27
3. a)4,1/12*1,5/7=49/12*12/7=7*12/12=7
7-5,2/9=(7*9-47)/9=16/9
16/9*3/8=2/3
b) (3/8+2,1/7*1,1/20)*1,1/3=
=(3/8+15/7*21/20)*4/3=(3/8+9/4)*4/3=(3+18)/8*4/3=(1+6)/2=7/2=3,5