If a point if chosen inside of the square what is the probability that it will also be inside the circle

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

At noon a tank contained 10cm water. after several hours it contained 7cm of water. what is the percent decrease of water in the tank?

What are the interpretations of the line 3x - 15y = 60? x-intercept y-interception a: x 20 - y -4 b: x 5 - y 20 c: x -3 - y 15 d: x -4 - y 20