How many significant figures are in 0.040?

Answer 1

Two.

There are rules of Significant figure is:

RULE #1 - All digits 1 through 9 are significant.

RULE #2 - Zero is significant when it is between two non-zero digits.

RULE #3 - A terminal zero to the right of a decimal point in a number greater than one is significant.

RULE #4 - A terminal zero to the right of a decimal point in a number less than one is significant.

RULE #5 - A zero used to fix a decimal point in a number less than one is not significant.

by Salim Reza

Answer 2

Zeros must be kept to show the decimal point or to indicate that zero is a significant figure.

In this question the 0.0 part of the number is to show the position of the decimal point and does not form part of the significant figure count.

If the number has been rounded to the nearest ten-thousandth then 0.0400 is correct to 3 sf.

If the number can be rounded to the nearest thousandth then it would be written as 0.040 and would be correct to 2sf.

If rounded to the nearest hundredth then it becomes 0.04 and is correct to 1 sf.

Answer 3

There are two significant figures in 0.040. The zeros to the right of the decimal point are not significant.

Answer 4

There are 2 significant figures.

Answer 5

2 of them.

Answer 6

Two.

Answer 7

Two