Your parents took your family out to dinner. the parents wanted to give the waiter a 15% tip. if the total amount of the dinner was $42,00 what should be paid to the waiter as a tip?

How to do this , and can some one explain

Could somebody me with this radical simplification?

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?