selesaikan operasi hitung berikut a.(-15–7)+(-20:4)= b.(-15×-8)–(-12:4)= c.-10 2/3+5 5/6–2 1/4=

a) (-15-7)+(-20:4)
    =(-22) + (-5)
    = - 27

b) (-15x -8)-(-12:4)
    = 120-(-3)
    = 123 

c) (-10[tex] \frac{2}{3} [/tex]) + ( 5 [tex] \frac{5}{6} [/tex] - 2[tex] \frac{1}{4} )
[/tex]
    = -[tex] \frac{85}{12} [/tex]
    = -7[tex] \frac{1}{12} [/tex]