A, B and C can individually completes a piece of work in 30, 50 and 75 days respectively. They worked on 1 day each with A starting the work followed by B the next day and C the next day. They continued working in this way till the 30th day after which the remaining work is completed by B and C working on alternate days starting with B on 31st day. In how many days was the work completed?
35
40
45
50