time word problem

[Stardust]

You have a staff of two clerks. Each clerk is able to file 10 messages in 15 minutes. Two hundred messages must be filed on a given day. If both clerks work at filing the messages, how many minutes will each take to do the task?

Please help with this question.

 

[Denis]

You have a staff of two clerks. Each clerk is able to file 10 messages in 15 minutes. Two hundred messages must be filed on a given day. If both clerks work at filing the messages, how many minutes will each take to do the task? Please help with this question.

Pretend you have 1 clerk able to file 20 messages in 15 minutes...