Well, 12 times 2 is 24, which is how many Manuel has.
Kendra has twice that, so she has 48.
Add 12, 24, and 48 together to get 84.
The answer is C.
Daniel -- 12 balls
Manuel -- 12 balls × 2 = 24
Kendra -- 24 balls x 2 = 48
12 + 24 + 48 = 84 balls total
Daniel has 12 tennis balls. Manuel has 24 tennis balls, and Kendra has 48 tennis balls. In total, they have 84 tennis balls.
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