1/2 of the base times the height is the area of a *?

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

Including 6% sales tax, an inn charges $135.68 per night. find the inns nightly cost

Suppose that in 2008 , 840,800 citizens died of a certain disease assuming the population of teh country is 399 miliion, what is the mortality rate in units of deaths per 100,000 people?