Mr. Scrooge bought 4 packages of ground beef. The second package weighed three times as much as the first, and the third package weighed half as much as the second. The fourth package weighed fifteen ounces, which was three ounces more than the third package. How many ounces of meat did Mr. Scrooge buy?

Question

Mr. Scrooge bought 4 packages of ground beef.  The second package weighed three times as much as the first, and the third package weighed half as much as the second.  The fourth package weighed fifteen ounces, which was three ounces more than the third package. How many ounces of meat did Mr. Scrooge buy?
Solve algebraically.
Please help me understand how to write the equation correctly, I’ve worked out the no. of ounces sold is 59 as well as how many ounces each package has
Package 4 = 15 ozs
Package 3  = 15 – 3 = 12
Package 2 = 12 x 2 = 24
Package 1 = 24 /3 = 8