Simplify this equation: (570.30−237.2)÷5.2

Question

I know the asnwer to this question  which is 64.0576 but the problem that i have is that I dont know how many sig figs the answer should have and if I have to round it. should it be 64.1?

Answer 1

The first operation is the one in parentheses, ie 570.30 - 337.2.  Since this is subtraction, you use the number of decimal places to give you the rounding parameter.  Thus, you would have 333.1 (to one decimal place).

Next operation is to divide this by 5.2, so you get 64.0577 and since this is division, the number of sig. figs. is dictated by the number with the least number of sig. figs, which in this case is the 5.2 with 2 sig. figs.  So, the answer should now be rounded to 2 sig. figs. which will be 64, and not 64.1 which has 3 sig. figs.