Juan went on a hiking trip. The first day he walked 18 kilometers. Each day since, he walked 90% of what he walked the day before. What is the total distance Juan has traveled by the end of the 10th day?

What is [tex] {7}^{98 + \sqrt{4} } - 3 \times (64 \div 2 + 4 - 36) \times a = a + 36[/tex]?

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15