Iodine-131 is a radioactive substance that decays at a rate of 8.3% every day. If a sample contains x grams of iodine-131 after 2 days, how much iodine-131 will it contain after 6 days?
a) 0.917^4 times x
b) 0.917^6 times x
c) 1.83^2 times x
d) 1.83^4 times x
e) 0.917^2 times x
f) 1.83^6 times x
b) 0.917^6 times x
After 2 days, the sample will contain 0.917^2 or 0.84155 times x grams of iodine-131.
To find out how much the sample will contain after 6 days, we need to multiply this amount by 0.84155 again: 0.84155 x 0.84155 = 0.917^4 or approximately 0.47359.
Therefore, after 6 days, the sample will contain approximately 0.47359 times x grams of iodine-131.