Element X decays radioactively with a half life of 13 minutes. If there are 530 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 11 grams?

72.7 minutes

Step-by-step explanation:

From the above question, we can deduce that we are to find the time(t) of decay.

The formula used for this calculation is given as:

N(t) = No(1/2)^t/t½

N(t) = quantity of the substance remaining = 11 grams

No = initial quantity of the substance = 530 grams

t = time elapsed

t½ = half life of the substance = 13 minutes

Making t , the subject of the formula

t = t½ × In(N(t)/No)/-In2

t = 13 × In(11/530)/-In2

t = 72.675420100572minutes

Approximately 72.7 minutes

answer: 5000

step-by-step explanation:

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you