Solve tangent 195 using sum and difference formula

Peaches cost $4.29 per pound. find the cost of two and a quarter pounds of peaches.

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

I’m still confused on how to work the percentages