When 430 randomly selected lightbulbs were tested in a laboratory 224 lasted more than 500 hours. Find a point estimate of the proportion of all lightbulbs that last more than 500 hours

Consider a cube that has sides of length l. now consider putting the largest sphere you can inside this cube without any point on the sphere lying outside of the cube. the volume ratio -volume of the sphere/ volume of the cube is 1. 5.2 × 10−1 2. 3.8 × 10−1 3. 1.9 4. 2.5 × 10−1 5. 3.8

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?