Subtraction is a mathematical operation. The best policy to buy is a 20-year term policy.
Subtraction is a mathematical operation that reflects the removal of things from a collection. The negative symbol represents subtraction.
Since we want the policy to last till the younger child is 22 years. And the present age of the younger child is 3 years. Therefore, the period for which the policy must work is 19 years (22-3).
Therefore, the best policy to buy is a 20-year term policy.
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