Final answer:
5.3 can be the difference of two numbers with thousandths places not equal to zero, as the digits after the decimal cancel out in the subtraction. Zeros are only considered significant when they are not merely serving as place keepers.
Step-by-step explanation:
Yes, 5.3 can indeed be the difference of two numbers, even if the numbers include digits in the thousandths place that are not zero. For example, you could have two numbers like 6.345 and 1.045; their difference is 5.3.
What matters is that the digits after the decimal in the difference cancel each other out when subtracted, resulting in a difference with no digits beyond the tenths place.
Understanding zeros in the context of significant figures is also crucial. Zeros between non-zero digits are always significant.
However, when they serve as place keepers to the right of the decimal point and there are no nonzero digits to the right, like in 5.3, they are not considered significant.