The sum of the numbers 436.32, 227.2 and 0.301 in appropriate significant figures is

Rules for Adding Significant Figures

(i) Count the number of significant figures in the decimal portion of each given number.

(ii)The digits to the left of the decimal place are not used to determine the number of decimal places in the final answer.

(iii) Add or subtract the given numbers in the normal way.

(iv) Round the answer to the LEAST number of places in the decimal portion of any number in the problem.

Here,

436. 32

+ 227. 2

+ 0. 301

663. 821

Here, 436.32 has 2 digits after decimal, 227.2 has 1 digit after decimal and 0.301 has 3 digits after decimal. According to rules the final result will have the least no. of digit after decimal i.e. 1 here.

Therefore, the final sum is 663.8