I need an answer to a question and i just can't get a close answer with any formula i find! sooo.. here it is.. if anyone can help thatd be awesome!!

What is the volume of a frustrum of a right pyramid with the area of the lower base equal to 100 sq in., the area of the upper base equal to 25 sq in., and the altitude equal to 12in.???

What is the volume of a frustrum of a right pyramid with the area of the lower base equal to 100 sq in., the area of the upper base equal to 25 sq in., and the altitude equal to 12in.???