How to write half a quantity and a third is twelve

Evaluate Cos(30°+45°) in surd form

James has $1100 invested at r% and $900 invested at (r+1)%. If his annual income on these two investments is $99,[..]

The total imports of petroleum (in millions of barrels per day) in a given year is approximated by the polynomial[..]

Lilian has part of $9000 invested at 4% and the remainder at 6%. His annual return on each investment is the same.[..]

Joe and Renee are building a fence. Joe can build a fence alone in 4 hours. If Renee starts helping Joe after he has[..]

Juan worked twice as many hours as jerry. Marcia worked 3 more hours than jerry. If they worked a total of 35 hours,[..]

A rectangular prism has a volume of 13,200 cubic feet. The base has an area of 660 square feet and all three[..]

Nancy leaves the school and drives toward her town at 27 mph. Greg leaves the same school 2 hours later and drives[..]

Bob can type 2 letters in 4 hours while Bill can do it in 6 hours. How many hours would it take them to type six[..]