1a. 16 - 4+2=14 ; b. -24-4+3 =-25; c. -24- 2.25-4 = -30,25 ; d. 4 - 16/9+3/4 =107/36
2a. 2/2=1 ; b. 1/1 =1 ; c. 1.25/1.5=0.25/0.3 ; d. 13/4 / 5/2 = 13/10
3a. 5/1 =5 ; b. 20/6=10/3 ; c. 5/6 / -1/6 = -5 ; d. 2.4-1.6 / -2.4-0.4 = 2
4 (Cred) a. a∈R/ {4} ; b. x∈R/ {-3} ; c. a∈R, b∈R/{-3} ; d. b∈R, a∈R/{40/3} ; e. a∈R. x∈R/ {3,-3} ; f. x∈R, a∈R/{-0.6 , 0.6}