Jannie said that 1 2/3 times 9 1/4 is 15.416. Mack said that 1 2/3 times 9 1/4 is 18.75. Is Jannie or Mack right. Show your work. Jannie is right because when you do 1 2/3 times 9 1/4 on a piece of paper or calculator, you will get what Jannie got. (15.416). Mack would have been right if the equation was 1 2/3 times 11 1/4.