Please solve the question and give correct answer with explanation so that i can understand it

Mathematics

1 answer:

denis-greek [22]2 years ago

6 0

Answer:

Step-by-step explanation:

Let the speed of the car is c and speed of the plane is p.

<h3>We are given:</h3>

The speed of the plane is 7 times the speed of the car

p = 7c

The distance traveled is

d = 315 km

The time difference to travel this same distance is 3 hours.

d = ts, where d- distance, t- time, s - speed

Find the time for car and plane and their difference.

t = d/s = 315/c

<h3 /><h3>Plane</h3>

t = d/s = 315/p = 315/(7c) = 35/c

<h3 /><h3>The difference</h3>

315/c - 45/c = 3

<u>Solve it for c:</u>

(315 - 45)/c = 3
270/c = 3
c = 270/3
c = 90 km/h

Now find the speed of plane:

p = 7c = 7*90 = 630 km/h

As we see, Jenny is right

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