Add, and give your answer to the correct number of significant digits.
12 cm+0.031 cm+7.969 cm =
20.00cm was wrong, is it 20.000cm as that is the most decimal places shown? yet 4 sig figs is the most shown in the question. or is 20cm correct as the decimals become insiginificant?
143 cm +289.25 cm + 68.45cm + 6.00cm = 506.70cm was also wrong
nonzero digits are significant, so it would be 20cm and 506.7cm