CEMC Pascal, 2015

Algebra Difficulty 1.2 Junior Find the answer Canada

The average age of Andras, Frances and Gerta is 22 years.

Name	Age (Years)
Andras	23
Frances	24
Gerta	?

What is Gerta’s age?

Pick one

Solution

Since the average of the three ages is 22, then the sum of the three ages is $3\cdot 22 = 66$ .

Since Andras’ age is 23 and Frances’ age is 24, then Gerta’s age is $66-23-24=19$ .

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