A can complete a certain work in 30 days. He started the work. After 4 days, B joined him and the whole work was completed in 10 days from the beginning. B alone can complete one-third of the same work in:
A, B, and C can complete a work in 40, 60, and 80 days respectively. They started working together. If A and B left 11 days and 8 days before the completion of work. In how many days they will complete the work.
The tops of two poles of height 24 m and 36 m are connected by wire. If the wire makes an angle of 60° with the horizontal, then the length of the wire is.