Element X decays radioactively with a half life of 9 minutes. If there are 960 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 40 grams?

y=a(.5)^t/h

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Write a ratio and a percent for the shaded area. it is 3x3 and 5x5 grid there is 6 shaded out of a. 6 over 25 , 30% b. 3 over 50 , 6% c.6 over 25 , 24% d. 3 over 10 , 30%