Definition
Checking a solution
Checking a solution means testing whether a proposed answer satisfies the original calculation, conditions, units, and context.
What it means
Put the answer back into the problem and test it. A strong check uses a different route from the one that produced the answer, because repeating the same work can repeat the same mistake. Also check whether the size and units make sense.
Remember it
Put the answer back and make it prove itself.
Example
A puzzle says 3 equal bags plus 2 loose counters make 20 counters. The proposed solution is 6 counters per bag. Check it by substitution: 3 × 6 + 2 = 18 + 2 = 20. The result matches the original total, so 6 passes the check.
Watch for
Doing the identical calculation again is a weak check if the same unnoticed error can happen twice.
Common mix-up
Checking asks whether a proposed answer works; solving is the process used to find that answer.
Exact meaning
Checking a solution is the verification of a proposed answer against the original problem, using substitution, inverse operations, estimation, another representation, or another systematic test to confirm that all required conditions are satisfied.