求1\3+2\15+2/35+1/63+7/99的值
1个回答

1/3+2/15+2/35+1/63+7/99

=(1/3+2/15+2/35+2/63+2/99)-1/63+5/99

=(1/3+1/3-1/5+1/5-1/7+1/7-1/9+1/9-1/11)-1/63+5/99

= 2/3-1/11-1/63+5/99

= 41/63-4/99

= 423/693

= 47/77