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valkas [14]
3 years ago
12

Jeff was already 7 miles out of town when his sister

Mathematics
1 answer:
Nikolay [14]3 years ago
5 0

The sister catches up Jeff after 2 hours

Step-by-step explanation:

We can write Jeff's position and his sister position at time t using the following expressions:

- Jeff position:

x_j(t) = 7 + 2.5 t

where:

7 is the initial position of Jeff when his sister sarts chasing him

2.5 is Jeff's velocity (in miles/hour), so its position increases by 2.5 miles for each hour

t is the time measured in hours

- Sister position:

x_s(t) = 6t

where

6 is the sister velocity (her position increases by 6 miles for every hour)

t is the time measured in hours

The sister catches up Jeff when the two positions are equal, so

x_j(t) = x_s(t)\\7+2.5t=6t

And solving for t,

7+2.5t-2.5t=6t-2.5t\\7=3.5t\\t=\frac{7}{3.5}=2 h

So, the sister catches Jeff after 2 hours.

Learn more about speed:

brainly.com/question/8893949

#LearnwithBrainly

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What is the lateral area of a right cylinder if the radius of the base is 12 mm and the altitude of the cylinder is 5 times the
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I have attached a diagram of the triangle described.

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