2019 AMC 10A Problems/Problem 3

Revision as of 17:41, 9 February 2019 by Baolan (talk | contribs) (Solution)

Problem

Ana and Bonita were born on the same date in different years, $n$ years apart. Last year Ana was $5$ times as old as Bonita. This year Ana's age is the square of Bonita's age. What is $n?$

$\textbf{(A) } 3 \qquad\textbf{(B) } 5 \qquad\textbf{(C) } 9 \qquad\textbf{(D) } 12 \qquad\textbf{(E) } 15$

Solution

Let A be the age of Ana and B be the age of Bonita.

A-1 = 5(B-1) A = B^2 We can solve for B to get B = 4 Then that means that A = 16. 16-4 = (D) 12

Solution by Baolan (someone please LaTeX this)

See Also

2019 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 2
Followed by
Problem 4
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 10 Problems and Solutions

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