Working together, A, B and C can finish a piece of work in 3 hours. A finishes the same work in 8 hours and B finishes it in 6 hours. How long will it take for C alone to finish the same work?
X, Y and Z can do a piece of work in 46 days, 92 days and 23 days, respectively, X started the work. Y joined him after 2 days. If Z joined them after 8 days from the beginning then for how many days did X work?
From the top and bottom of a straight hill, the angle of depression and elevation of the top of a pillar of 10 m height are observed to be 60° and 30° respectively. The height (in metres) of the hill is