Estimate the following using general rule:
$$28,292 - 21,496$$
$$28,292 - 21,496 :-$$
By rounding off to nearest thousands, $$28296$$ rounds off to $$28000$$ and $$21496$$ rounds off to $$21000$$
$$28000$$
$$-21000$$
$$........$$
$$7000$$
$$........$$
The difference of these two numbers is $$7000.$$