Report the result of the following calcualtions to the correct number of significant figures.

a) 8.25 x 0.14

Answer

When this mutiplication is carried out the result is 1.155. This result has 4 significant figures, but according to our rules for significant figures in multiplication and division the result should only have 2 sig figs. The reason the result should be reported to 2 sig figs is because the number 0.14 has 2 sig figs (the number 8.25 has 3 sig figs). So we must round this number to the 2 sig figs.

According to the rounding rules we look at the left most digit to be dropped which in this case is a '5'. The rule says, if this digit is '5' or greater, or is '5' followed by nonzero digits, add '1' to the last digit to be retained and drop all the digits further to the right.

So result must be reported as 1.2.