tolong yg bisa no 7,8,9 terima kasih

Nomor 7:
3 1/4 - 2 3/4 + 2 1/2 = 13/4 - 11/4 + 10/4 = 12/4 = 3

Nomor 8:
L.alas balok =p x l
V.balok=p x l x t

Tinggi=> t=volume:luas
20/16 dibagi 10/4 =2/4 = 1/2


Nomor 9:


(2 1/2 x 0,25) + (1 1/8 : 3/4) = (5/2 x 1/4) + (9/8 : 3/4) = 5/8 + 3/2 = 5/8 + 12/8 = 17/8 = 2 1/8