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 = 17.4 minutes

Step-by-step explanation:

p = a(1/2)^(t/h)

121 = 900(1/2)^(t/6)

Divide both sides by 900

0.1344444444 = (1/2)^(t/6)

Take the log of both sides

log0.1344444444 = (t/6)log(1/2)

Divide both sides by log(1/2)

log0.1344444444 / log(1/2) = t/6

multiply both sides by 6

6 * log0.1344444444 / log(1/2) = t

use calculator

17.369507726516199 = t

rounded

t = 17.4 minutes

1 x=22.52

2: 65/39=604+39x

65x-39x=604

26x=604

x=604/26

×=23.23