9/11 ×4/9×66=（9/11×4/9）×66=4/11×66=4×6=24
3/8×2/3×4/7=（3/8×2/3）×4/7=2/8×4/7=1/4×4/7=1/7
15/28×42/55×11/13=（15/28×42/55）×11/13=3/2×3/11×11/13=3/2×3/13=9/26
15/12×52×1/13=5/4×52×1/13=（5/4×1/13）×52=5/52×52=5
计算.有些麻烦你打,答得好的我马上采纳.
9/11 ×4/9×66=（9/11×4/9）×66=4/11×66=4×6=24
3/8×2/3×4/7=（3/8×2/3）×4/7=2/8×4/7=1/4×4/7=1/7
15/28×42/55×11/13=（15/28×42/55）×11/13=3/2×3/11×11/13=3/2×3/13=9/26
15/12×52×1/13=5/4×52×1/13=（5/4×1/13）×52=5/52×52=5