4/7 × 5/9 + 3/7 × 5/9 简算,
问题描述:
4/7 × 5/9 + 3/7 × 5/9 简算,
答
4/7 × 5/9 + 3/7 × 5/9
=(4/7+3/7)x5/9
=1x5/9
=5/9