How many significant figures are there in the number 1008500?

1 Answer
Aug 20, 2016

Answer:

Explanation:

The first thing to look for when deciding how many significant figures you have in a value is the number of non-zero digits it contains.

Non-zero digits are always significant, so right from the start you know that your number will contain at least as many significant figures as the number of non-zero digits it contains.

In this case, you have #1#, #8#, and #5# as non-zero, and thus significant, digits.

Now, your number also contains two sandwiched zeros. By definition, a sandwiched zero is a zero that follows and is followed by at least one non-zero digit. Sandwiched zeros are always significant.

In your case, you have

#1color(red)(00)8500 -># two sandwiched zeros, significant

Here two zeros follow #1#, a non-zero digit, and are followed by #8# and #5#, two non-zero digits

Finally, your number also contains two trailing zeros. Trailing zeros are zeros that follow at least one non-zero digit and are not followed by other non-zero digits.

When trailing zeros do not follow the decimal point, they are not significant. In your case, you have

#10085color(purple)(00) -># two trailing zeros, NOT significant

Therefore, you can say that your number has #5# significant figures

#1color(red)(00)85color(purple)(00) -> { (3color(white)(a) "non-zero digits, signifcant " color(green)(sqrt())), (color(red)(2)color(white)(a)"sandwiched zeros, significant "color(green)(sqrt())), (color(purple)(2)color(white)(a)"trailing zeros, NOT significant "color(red)(xx)) :}#