In 1979 Mr. Jackson bought a total of n shares of stock X and Mrs. Jac

In 1979 Mr. Jackson bought a total of n shares of stock X and Mrs. Jackson bought a total of 300 shares of stock X . If the couple held all of the respective shares throughout 1980, and Mr. Jackson's 1980 dividends on his n shares totaled $150, what was the total amount of Mrs. Jackson's 1980 dividends on her 300 shares?

(1) In 1980 the annual dividend on each share of stock X was $0.75.
(2) In 1979 Mr. Jackson bought a total of 200 shares of stock X.