A and B can do a job in 10 days and 5 days, respectively. They worked together for two days, after which B was replaced by C and the work was finished in the next three days. How long will C alone take to finish 40% of the job?
A room has 5 doors, if a person enters through a dooor,
that person cannot leave through that same door. Find the number
of ways that person can enter and leave that room.
When the expression x³+ax²+bx+c is divided by x²-4, the remainder is 18-x, and when it is divided by X+3 the remainder is 21. What is the remainder when the expression is divided by X+1?
Algebra
Pipe A can fill a tank in two hours and pipe B can fill it in half the time it takes pipe C to empty it. When all 3 are opened, it takes 1.5 hours to fill the pool how much time is required for pipe 'C to empty the tank?