Average Problem 1

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Samantha along with a partner is playing in a tennis double tournament.
According to the rule, the pair of players must have an average age of ten
years or younger. The age of Samantha is eight years. What is the age of her partner?

Solution: Let the age of the partner of Samantha be x years.
Given, (x + 8)/2 = 10 or less
⇒ x + 8 = 10 x 2 = 20 or less (multiplying both sides by 2)
⇒ x = (20 – 8) or less
= 12 years or less