Task: Question Answering
Input (English): Problem: a can do a half of certain work in 70 days and b one third of the same in 35 days. they together will do the whole work in ?
Options: a. 1 / 65, b. 1 / 62, c. 1 / 63, d. 1 / 60, e. 1 / 61
Output (English): d