20.96-4.67-5.33
=20.96-(4.67+5.33)
=20.96-10
=10.96
（3/8＋7/24-1/6）×48
=3/8×48 ＋7/24×48 -1/6×48
=18+14-8
=24
69÷（0.8＋0.6×2.5）
=69÷(0.8+1.5)
=69÷2.3
=30