A group of 25 math teachers showed that they spent an average of 11 minutes per student correcting students’ exams. Find the 90% confidence interval of the meantime for all exams when there is a standard deviation of 2.3 minutes.

Cora bought a package of erasers. there are 4 pink erasers and 12 blue erasers. what is the ratio of pink erasers to blue erasers?

Math each whole number with a rational,exponential expression

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?