(1) A = 10 days; B = 15 days; C = 18 days

       (1) 0    (2) 1        (3) -1         (4) Does not exist

4 workers produce 1400 toys in 5 days. After one days work was over, 14 more workers joined them. In how many days can they complete the remaining work?

1)  2

2)  3

3)  4

4)  3 1/2