39:3*4 64:2*3 48:4*8 100-3*4 6*9+48:6 66:3*2-5 84-(48+26) 23+(75-48) 53-(53-40)
39:3×4 = 13×4 = 52 64:2×3 = 32×3 = 96 48:4×8 = 12×8 = 96 100-3×4 = 100-12 = 88 6×9+48:6 = 54 + 8 = 62 66:3×2-5 = 22×2-5 = 44-5 = 39 84-(48+26) = 84 - 74 = 10 23+(75-48) = 23 + 27 = 50 53-(53-40) = 53 - 13 = 40