A class of 30 music students includes 13 who play the piano, 15 who play the guitar, and 9 who play both the piano and the guitar. How many students in the class play neither instrument?

What are the relative frequencies to the nearest hundredth of the columns of the two-way table?

If 24 people have the flu out of 360 people, how many would have the flu out of 900. choose many ways you could use proportion that david would use to solve this problem

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60