Question

А) 4 5/12 + ( 5 1/12 - 3 4/21

Answer 1

4*5/12=1,66
5*1/12=0,41
3*4/21=0,16
1,66+(0,41-0,57)=1,66-0,16=1,5

Answer 2

4 5/12 + ( 5 1/12 - 3 4/21)53/12+(61/12-67/21)      /3
53/4+(61/4-67/7)
53/4+(427/28-268/28)
53/4+159/28
371/28+159/28
530/28