Using the rules for significant figures, what do you get when you subtract 15.54 from 508.9538?

Solution:

We have to subtract 15.54 from 508.9538.

15.54 → two decimal places

508.9538 → four decimal places

So, the answer must have two decimal places.

Now, 15.54 - 508.9538 = -493.4138

The result has four decimal places.

So, we have to round it to match the fact that the answer can only have two decimal places.

So, count two decimals -493.4138

Since the third decimal i.e. 3 is smaller than 5, we can round this off to -493.41

Therefore, the result of subtraction is -493.41

Example:

Using the rules for significant figures, what do you get when you subtract 16.64 from 510.9576?

Solution:

We have to subtract 16.64 from 510.9576.

16.64 → two decimal places

510.9576 → four decimal places

So, the answer must have two decimal places.

Now, 16.64 - 510.9576 = -494.3176

The result has four decimal places. So, we have to round it to match the fact that the answer can only have two decimal places.

So, count two decimals -494.3176

Since the third decimal i.e. 7 is larger than 5, we can round this off to -494.32

Therefore, the result of subtraction is -494.32

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Using the rules for significant figures, what do you get when you subtract 15.54 from 508.9538?

Summary:

Using the rules for significant figures, when you subtract 15.54 from 508.9538 you get -493.41