Suppose that there is parity between the Australian dollar and the United States dollar. Let x be a positive number and assume that the United States dollar increases by 100x % in Australian dollars. (show calculation)

(a) Calculate the percentage decrease for one Australian dollar in United States dollars in terms of x. Simplify your answer.

(b) Using your answer to (a), if the United States dollar increases by 10% in Australian dollars, calculate the percentage change for one Australian dollar in United States dollars.