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2025 AMC 12A Problem 1

Problem 1 of 25EasierAlgebra

Andy and Betsy both live in Mathville. Andy leaves Mathville on his bicycle at 1:30,1{:}30, traveling due north at a steady 88 miles per hour. Betsy leaves on her bicycle from the same point at 2:30,2{:}30, traveling due east at a steady 1212 miles per hour. At what time will they be exactly the same distance from their common starting point?

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Solution

Let tt be the number of hours since 1:30.1{:}30. Andy has traveled 8t8t miles north, and Betsy, who started an hour later, has traveled 12(t1)12(t-1) miles east. Setting the distances equal, 8t=12(t1),8t = 12(t-1), so 4t=124t = 12 and t=3.t = 3. Three hours after 1:301{:}30 is 4:30.4{:}30. Thus, the correct answer is E.

More practice

Concepts: distance rate and time · linear equation

Problem text and solution from the LIVE past-contest archive. See also the AoPS wiki page for community solutions.