[tiarakiyoshi]

I haven't been able to obtain a clear answer as to when to use significant figure rules in mixed operations. Take the example.

320.55 - (6104.5/2.3)

Do you calculate the parentheses first (order of operations) and use the significant figure rule for multiplication and division for 320.55 - 2700, and then subtract and apply the addition/subtraction rule for -2379?

[Mitch]

sounds good

[tiarakiyoshi]

Excellent. Thank you very much.

[Borek]

Note that significant figures are very lousy defined.

Take numbers 1 and 9.

Both have 1 significant digit.

That means that first value represents something between 0.5 and 1.5 (so it is 1 +/- 50%) while the second something between 8.5 and 9.5 (so it is 9 +/- 6%).

Depending on the value accuracy is either 50% or 6%. That's - at least - suspicious.