How many points are found at the intersection of a line and plane

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.

Chuck is making a salad to go with his soup. the recipe calls for 2.1 cups of lettuce per person and 0.56 ounces of salad dressing per cup of lettuce. if 11 dinner guests want salad, how many ounces of dressing will be necessary? round the answer to the nearest whole ounce. 1 ounce 2 ounces 6 ounces 13 ounces

What is 0.625 as a % ? ? i dont know math