I am trying to determine the number of sig figures.

Question

The question is 234.56 + 8.04 + (3.2 x 10^2) I got the answer of 562.6 but its marked wrong and Im not sure what I did wrong.

Answer 1

When expanded, 3.2 x 10² is 320 (no decimal point, 2 significant figures). When reading from left to right, the "2" in the tens place is the last significant figure. Of the three values being added together, this "2" is in the position farthest to the left, so the answer may have significant figures only in this position (tens) and any to the left.

 

    234.56

       8.04

+ 320

              

   562.60 can have only 2 significant figures, the 5 in hundreds place and the 6 in tens place.

 

The correct answer would be 560 (no decimal point)