word problem below

Question

Seven hundred grams of a radioactive material decays according to the formula
A = 700

(2/3)^t

,
where t is measured in years. Find the amount present in 10 years. Round to the nearest one-tenth of a gram.

Answer 1

Just plug t = 10 into the formula and evaluate.  That is all there is to it.

 

A(t) = 700 (2/3)^t grams

 

A(10) = 700 (2/3)¹⁰ grams = ? grams

 

You can finish from here.