How much would a 15% tip be on a bill that cost $85?

What expression is equivalent to 1/2(2+3x-6)

You are on a cycling trip around europe with friends. you check the weather forecast for the first week. these are the temperatures for the week. sun mon tues wed thurs fri sat 16°c 20°c 24°c 28°c 28°c 23°c 15°c what is the mean temperature forecast for the week?

How many $20 bills do you need to have to make $280