Question

二分之一加六分之一加十二分之一等等加到九十九分之

Answer 1

应该是加到90分之1

1/2+1/6+1/12+……+1/90

=1/1×2+1/2×3+1/3×4+……+1/9×10

=1-1/2+1/2-1/3+1/3-1/4+……+1/9-1/10

=1-1/10

=9/10