How many moles of ammonia contain each of the following number of molecules?

Note: Reference the Fundamental constants table for additional information.

Part 1 of 3
Be sure your answer has the correct number of significant figures.

1.53x10^25 molecules= round answer to the correct significant figure
1.11x10^22 molecules
6.4x10^23 molecules=

1.53x10^25 molecules = 0.254 moles

1.11x10^22 molecules = 0.184 moles
6.4x10^23 molecules = 10.6 moles