Question

1乘3分之2002+3乘5分之2002+5乘7分之2002+7乘9分之2002等于多少

Answer 1

答：

1乘3分之2002+3乘5分之2002+5乘7分之2002+7乘9分之2002

=2002/(1×3)+2002/(3×5)+2002/(5×7)+2002/(7×9)

=1001×(1-1/3+1/3-1/5+1/5-1/7+1/7-1/9)

=1001×(1-1/9)

=1001×8/9

=8008/9