The extended family arranged marriage, ................. individuals were consulted on the choice of their mate

1/1.2+1/2.3+1/3.4+......+1/999.1000

=> 1/1-1/2+1/2-1/3+1/3...-1/999+1/999-1/1000

=> 1-1/1000

=>1000/1000-1/1000

=> 999/1000

(x-2)(x+2)-(x+1)^2+(x+1)(x+2)

Số A là:

    \(\sqrt{11111}\) = 105,4087283

           Đáp số:105,4087283