significant numbers
2.8723 * 1.6 = 4.59568. Is it 4.6 because it is the smallest number you are multiplying it by in the sum? e.g. 2.8723 has 5 signifigant figures but 1.6 has 2 so the answer has no more than 2.Smallest number of significant figures.
With addition is it the smallest number afte the decimal point e.g. 3.968 + 2.02 + 4.7832 = 8.0374 = 0.05 because it is the smallest number of decimal places in the sum is 1. e.g. 2.02 = 1 significant figure after decimal point?