Give the answer to the following calculation with the correct number of significant digits. Report your answer in scientific notation.

(6.17 x 10-1 + 4.9 x 10-2) x (3.95 x 10-2 + 6.454 x 10-3)

i know the answer is 0.0306, but how many sigfigs should the final answer have? please help!

2 answers

opps, I missed something earlier.

In the case of adding numbers, you cannot make rightmost zeroes significant. adding...
.627 + .049 makes a three digit number, since the thousands digit in both numbers is sig.
.0395 + .006454 here is a problem. In this, the first number is sig to the thousandths, so the secnd number can only be added to that significance..
.0395 + .0065= .0460 is a three sig number.
Finally, the answer will be a 3 x 3 multiply, so the answer will be to three sig digits.
Here us a site that may help.

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