A/B = C/D is the general template for a proportion. In this case,
A & B represent the distances Charli rides her bike
C & D represent the time values that pair up with A and B in that order
We are given
A = 6000 meters, B = 15 minutes, C = unknown, D = 2 minutes
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So we have this updated equation
6000/15 = C/2
Let's cross multiply and isolate C
6000*2 = 15*C
12000 = 15C
15C = 12000
15C/15 = 12000/15 ... divide both sides by 15
C = 800
