计算下列各题.(能简算的要简算).

3/8×10/11+5/8÷11/10
=3/8×10/11+5/8×10/11
=（3/8+5/8）×10/11
=1×10/11
=10/11
48×（11/24-5/12+3/8）
=48×11/24-48×5/12+48×3/8
=22-20+18
=20
2.4-2.4×4/7-3/7
=2.4×（1-4/7）-3/7
=2.4×3/7-3/7
=（2.4-1）×3/7
=1.4×2/7
=0.4
3×（2/15+1/12）-2/5
=3×2/15+3×1/12-2/5
=2/5-2/5+3/4
=3/4