Mrs. Cahn asks her students to write 0.40 as a fraction. Isaac wrote 4/10
Colleen wrote 40/100.
Explain how both students are correct.
Use words and a pictorial model (using the scratch pad) to explain your answer.

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

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

Ade and abc are similar. which best explains why the slope of the line between points a and d is the same as the slope between points a and b?