Can someone explain subtraction and addition in literal fractions pls i have a test tomorrow

Which ordered pair is a solution to the system of linear equations? 2x + 3y= 6 –3x + 5y = 10

What is the percentile for data value 6 in the following data set? 4 13 8 6 4 4 13 6 4 13 2 13 15 5 9 4 12 8 6 13 40 25 35 62

The krasnapolski is a top-of-the-line hotel in amsterdam, the netherlands. among their many services, they rent bicycles to guests. the bicycle checkout is open 24 hours per day 7 days per week and has 50 bicycles on hand. on average, 10 guests request a bicycle each day, arriving completely randomly at all times of the day during the spring and summer seasons. guests keep bicycles for four days on average, with a standard deviation of two days. how long does a guest on average have to wait for a bike? a. approximately 24 hours b. approximately 0.033 hours c. approximately 4 days d. approximately 47 minutes