Question

Solving a math word problem.

question in comments

Answer 1

http://gyazo.com/eccd808fc3f707de0b7df93ef4b26bf9

^^question

Answer 2

@iGreen

Answer 3

For every half-life you divide the mass by 2. So for the first half life you take the initial mass, 180g, and half it, leaving 90g. The second halflife would half that mass, leaving 45g, and the third would half again leaving 22.5g

Answer 4

ohhhh

Answer 5

@LastTrainHome22 i have another one http://gyazo.com/ada1271c1f1cb16619b90a539c7c9d9e

Answer 6

In this one its easier to think of it in terms of how much land if left each instead of how much is being removed. If 3.25% is being removed each year, that means 96.75% will remain.

So for each year to find the area remaining you can multiply the initial area by 0.9675.

You can either do that 12 times for the long and time consuming way, or you can just multiply the starting area by \[0.9675^{12}\]

Answer 7

i multiplied it but didnt get the right answer

Answer 8

It is not 2219.86 km?