2019 AMC 10A Problems/Problem 3
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Contents
Problem
Ana and Bonita were born on the same date in different years, years apart. Last year Ana was
times as old as Bonita. This year Ana's age is the square of Bonita's age. What is
Solution
Solution 1
Let be the age of Ana and
be the age of Bonita. Then,
and
Substituting the second equation into the first gives us
By using difference of squares and dividing, Moreover,
The answer is
See Also
2019 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 2 |
Followed by Problem 4 | |
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All AMC 10 Problems and Solutions |
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