<span>Changing the grouping of the addends should not change the sum, according to the associative property of addition. You might group them differently with (50 + 3) + 47, so that you have 50 + (3 + 47). You might not regroup them with (16 + 4) + 5 rather than 16 + (4 + 5).</span>
Well it depends if it's a leap year. If it isn't a leap year there are 28 days and if we are in a leap year than there are 29 days in February.
Hope that helped :)
