Element X decays radioactively with a half life of 6 minutes. If there are 900 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to
decay to 121 grams?
y = a(.5)^(t/h)

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

I'm confused on this could anyone me and show me what i need to do to solve it.

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. 4x^2 + 20x + 25 = 0