A man bought a watch, a chain, and a locket for $216. The watch and locket together coast three times as much as the chain, and the chain and locket together cost half as much as the watch. What was the price of each?

Prove the formula for the cosine of the sum of two angles; and deduce the formulas for the cosine of the double of an angle and the cosine of the half of an angle.

Reduce the following expression to its simplest form: Reduce the following expression to its simplest form: (9a 2 b 2- 4b 4) (a 2- b 2) - (3ab - 2b 2) (3a [a 2 + b 2] - 2b [b 2 + 3ab - a 2])b

Latin grammar: Give the principal parts of cado, cacdo, tono, reperio, curro, pasco, paciscor, marking the quantity of the penult.