For Times Square magnets, we have that the price of each magnet is 2 dollars / magnet, there are 4 magnets / set, and Tom buys 12 sets. For Statue of Liberty magnets, the price is 3 dollars / magnet, there are 5 magnets / set, and Tom buys 12 sets
We can make a table of these values:
Magnets Price ($$/magnets) Set Size (magnets/set) Quantity (sets)
T.S. 2 4 12
S. of L. 3 5 12
Now, we can use the formula
Total Cost = Number of Magnets Bought * Price = (Quantity * Set Size) * Price
So we see that
Cost of T.S. magnets = Quantity * Set Size * Price
= 12 sets * 4 magnets * 2 dollars = $96
set magnet
Cost of S. of L. magnets = Quantity * Set Size * Price
= 12 sets * 5 magnets * 3 dollars = $180
set magnet
So the total amount spent was $96 + $180 = $276.