sig fig question?

Question

i dont really get this addition/ minus as well as division and multiplication

please show me the steps and explain it to me in simple English
and please solve these questions
500 - 3.7
500. -83.35

Answer 1

repeat to yourself "your answer is only as precise as the least number of significant figures in the operation"

In the first, lack of the decimal after the 500 implies one number significane. So the answer would be "500" .

In the second, the decimal implies 3 sign. fig. precision, so you would do the subtraction and round off to 3 significant figures. So the answer would be "417."