How many significant figures in 0.027090?

Answer 1

3.

Actually the answer is 5, for a number less than 1, all digits, including zeroes, count from the first non-zero digit.

You can always calculate the number of sig figs if you put the number into scientific notation. Trailing zeroes after the decimal point indicate a known level of precision that just happens to be zero in this case.

So in this case it would be 2.7090 x 10-2.

Answer 2

Five. The last 0 is significant since otherwise is should not be there.

Answer 3

5 of them.

Answer 4

5 of them.

Answer 5

Five