GAUSS8 1998 Problem 16

Suppose that x^\ast means \frac1x, the reciprocal of x. For example, 5^\ast=\frac15. How many of the following statements are true?
(i) 2^\ast+4^\ast=6^\ast (ii) 3^\ast\times5^\ast=15^\ast (iii) 7^\ast-3^\ast=4^\ast (iv) 12^\ast\div3^\ast=4^\ast

Answer Choices
A. 0
B. 1
C. 2
D. 3
E. 4