In this problem, we will use amounts of the isotopes that are proportional to the actual amounts. Trust me, this is mathematically sound. suppose you have a samle of potassium feldspar from a rhyolite and you measure the ratio of atoms of 40

AR to 40K of .024 to 1, or for every 10000 atoms of 40k you find 240 atoms of 4o
AR.
a. what is the ratio of atoms of radiogenic 40Ca to radiogenic 40
Ar.

b. what is the ratio of atoms radiogenic 40Ca to 40k

c. What is the daughter parent ratio ((40Ca+40
Ar)/40K)?
d. For every 10000 atoms of 40K in the sample today, how many atoms of radiogenic 40Ca plus 40
Ar are there now?