I dont understand maths and that quote means nothing to me
half of 3 is 1.5 to my simple mind
Dont know how I got a B at GCSE.
This is an information issue. While 3/2 = 1.5, when we do math in science we never report more significant figures than exist in the number with the least significant figures in the operations. It ensure that we don't add a sense of higher accuracy which is a function of math rather than a function of precision of measurement. For example, if you have a scale that measures weight to the thousandths place, even though you can do math which results in digits beyond the thousandths place you don't report that or carry those digits into additional equations because we don't actually know what's happening at that level of accuracy. So yes, 3/2=1.5 but in some scenarios you won't report the answer to that level of accuracy.