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NISA [10]
3 years ago
7

Elena and Jada are 12 miles apart on a path when they start moving towards each other Elena runs at a constant speed of 5 miles

per hour and Jada walks a constant speed of 3 miles per hour how long does it take untill Elena and Jada meet? please explain answer. Thank you!
Mathematics
2 answers:
kirill115 [55]3 years ago
5 0
ANSWER

It took 1 hour 30 minutes

EXPLANATION

It was given that Elena and Jada are 12 miles apart.

This means that the distance between them is

d = 12 \: miles

We use the formula,

speed = \frac{distance}{time}

If Elena covers d miles in
t_1 \: hours

Then Jada will cover,
( 12-d) \: miles

in
t_2 \: hours

We were told that Elena runs at a constant speed of 5 miles per hour.

This implies that,
5 = \frac{d}{t_1}

t_1= \frac{d}{5} ...eqn1

and Jadda walks a constant speed of 3 miles per hour.

This implies that,

3 = \frac{12-d}{t_2}

This implies that,

t_2 = \frac{12-d}{3} ...eqn2

When Elena and Jada meets,then

t_2 = t_1

We equate the two equations and solve. This implies that,

\frac{d}{5} = \frac{12-d}{3}

We cross multiply to get,

3d = 5(12-d)

3d = 60-5d

This implies that,

8d= 60

d = 7.5

The time they met was after

\frac{7.5}{5} = 1.5\: hours
ankoles [38]3 years ago
3 0
If you really want to figure this out you make an equation to solve for the time
let's let
x = time from Elena to Jada and
x = time from Jada to Elena
12 then the equation
12 = 5x +3x
would help figuring out their distance say for one of them
12 = x(5+3)
12/8 = x
1.5 = x
1. 5 hours they will meet up
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Answer:

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Step-by-step explanation:

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3 0
4 years ago
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