Answer: 1:30 PM
It takes 30 minutes
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Explanation:
x = number of hours traveled
We'll use the equation
distance = rate*time
You bike at a rate of 12 mph and do so for x hours. That means you travel 12x miles based on the equation above. Your friend travels 4x miles for similar reasoning. Overall, the two of you travel a combined distance of 12x+4x = 16x miles. This combined distance is set equal to the 8 miles (distance between your houses) and you solve for x.
16x = 8
x = 8/16
x = 1/2
x = 0.5
Recall x is the number of hours, so that means it takes 1/2 an hour for the two of you to meet. This is equivalent to 30 minutes since 1/2*60 = 30.
If all of this starts at 1 PM, then you'll meet up at 1:30 PM since we add on 30 minutes to 1 PM to get to this moment in time.
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Extra info:
You travel 12x = 12*0.5 = 6 miles
Your friend travels 4x = 4*0.5 = 2 miles
Total distance = you+friend = 6+2 = 8 miles
This helps confirm the answer.