1/3*5+1/5*7+1/7*9+……1/97*99
=（1/3-1/5+1/5-1/7+1/7-1/9+……+1/97-1/99）÷2
=（1/3-1/99）÷2
=32/99÷2
=16/99
1/3*5+1/5*7+1/7*9+……1/97*99
1/3*5+1/5*7+1/7*9+……1/97*99
=（1/3-1/5+1/5-1/7+1/7-1/9+……+1/97-1/99）÷2
=（1/3-1/99）÷2
=32/99÷2
=16/99