The half-life of rubidium-89 is 15 minutes. If the initial mass of the isotope is 250 grams, how many grams will be left after 100 minutes?

Every minute, the first letter of each word is moved to the other end of the word. After how many minutes will the original sentence first reappear?

A total of 24 students are in alfred's class. the number of girls in the class is 3 more than twice the number of bullies write and solve a system of equations that can be used to find g the number of girls who are in a first class and be the number

In the equation Ax + By = C, A and B cannot both be zero. What if only A is zero? What if only B is zero? Explain.

Two brothers each purchase a new pair of hiking boots and two canteens. The hiking boots cost $34.00 each. The total of their purchase was $98.00. a. Define a variable: b. Write an equation: c. Solve:

0.471*6.379 rounded to the nearest tenth

A 3pack of boxes of juice costs 1.09. A 12 pack of boxes cost 4.49. A case of 24 boxes costs 8.78. Which is the best buy? Explain your reasoning

What is the answer to: 2.8 x 103 x 3.07 x 105 (written in scientific notation) ?

A restaurant orders corn tortillas and flour tortillas. The ratio of the number of corn tortillas to the number of flour tortillas is 2 : 3. What is the ratio of the number of flour tortillas to the total number of tortillas?

You want to estimate the number of eighth-grade students in your school who find it relaxing to listen to music. You consider two samples.

5 80/100 in decimal form