A box contains 10 blue water bottles, 7 green water bottles and 5 red water bottles.
Two water bottles are drawn from the box. In the first draw, a water bottle is randomly drawn from the box with no replacement. What is the probability that a green bottle will be drawn on the second draw?[2]
How many red water bottles should be added into the bag such that the probability of drawing a red water bottle on the first draw is \(\dfrac23\)?[2]