Which number has one significant figure: #4xx10^(-23)# or #4.0xx10^(-23)#?

2 Answers
Sep 19, 2015

It would be #4xx10^(-23)#. #4.0xx10^(-23)# would have two sig figs.

Sep 19, 2015

Answer:

the correct answer is #4xx10^(-23)#

Explanation:

#4xx10^(-23)# is one significant figure.

#4.0xx10^(-23)# is two significant figures since it contains a trailing zero in a number that has a decimal point.

Here is a full explanation on significant figures:
enter image source here

Source: Screenshot from my teaching notes.