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Sauron [17]
3 years ago
13

A girl ran to the store at a speed of 6mph, and walked back at 4mp. If her round trip took 15 minutes, how far away is the store

?
PLS HELPPP
Mathematics
1 answer:
MariettaO [177]3 years ago
6 0

Answer:

0.6 miles

Step-by-step explanation:

Let's say the store is x miles away, she walks to the store in a hours, and she walks back in b hours.

First, her total time = time walked there + time walked back = a + b = 15 minutes = 1/4 of an hour = 0.25 hours

a + b = 0.25 (because a and b are in hours)

distance = speed * time

x = 6 miles/hour * a hours = 6a miles

x = 4 miles/hour * b hours = 4b miles

If we can find a or b, we can find x.

4b = x = 6a

4b = 6a

a + b = 0.25

We now have two equations with two variables. Using substitution, we can solve for one of them

a + b = 0.25

subtract a from both sides to find b

0.25 - a = b

plug that into the other equation, 4b = 6a

4(0.25-a) = 6a

1 - 4a = 6a

add 4a to both sides to isolate a and its coefficient

1 = 10a

divide both sides by 10 to solve for s

a = 1/10 of an hour = 0.1 of an hour = 60 minutes / 10 = 6 minutes

6a = x

6(0.1) = x

0.6 = x

the store is 0.6 miles away

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