Ah, yes
if you start with P amount of something and the half life is h units (in years) and the time elapsed is t (in years) then the amount left is A
the equation is

so
given
h=1620
P=150
t=200
so


use your calculator
A≈137.69781917515g
about 138grams left
Answer:
307/500
Step-by-step explanation:
307 is a prime number.
The way to find this out is to take 0.614 and multiply it by 1,000 because then it will be a natural number. 0.614*1,000=614.
now you take 614/1,000 because that's what you multiplied it by and simplify it.
614/2 and 1,000/2=307/500 and this cannot be simplified any more than this because 307 is a prime number.
Answer:
the second one
Step-by-step explanation:
8.1 + 6.0 + 4.7 + 6.9 + 5.6 + 7.7 + 6.3 + 7.8 + 6.1 + 9.2 = 68.4/9 = 7.6