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An airplane consumes fuel at a constant rate while flying through clear skies, and it consumes fuel at a rate of 64 gallons per minute while flying through rain clouds.

Let C represent the number of minutes the plane can fly through clear skies and R represent the number of minutes the plane can fly through rain clouds without consuming all of its fuel.
56C+64R<9000
According to the inequality, at what rate does the airplane consume fuel while flying through clear skies, and how much fuel does it have before takeoff?

User Valbona
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2 Answers

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The given inequality is:

56C + 64R < 9000

We know that the airplane consumes fuel at a constant rate while flying through clear skies. Let the fuel consumption rate be F (in gallons per minute) and let the amount of fuel the airplane has before takeoff be T (in gallons).

We need to find the values of F and T that satisfy the given inequality.

First, we can simplify the inequality by dividing both sides by 8:

7C + 8R < 1125

Next, we can use the fact that the airplane consumes fuel at a rate of 64 gallons per minute while flying through rain clouds to write an expression for the total fuel consumption during R minutes:

64R

Similarly, the total fuel consumption during C minutes while flying through clear skies is:

FC

The total fuel consumption during both C and R minutes can be expressed as:

FC + 64R

We know that the total fuel consumption must be less than the initial amount of fuel, which is T. Therefore, we can write:

FC + 64R < T

Substituting FC = F * C, we get:

F * C + 64R < T

We can rearrange this inequality to solve for T:

T > F * C + 64R

Now we can use the inequality 7C + 8R < 1125 to solve for F and T.

Let's assume the airplane has enough fuel to fly for 1 hour (60 minutes) in clear skies and no rain clouds. Then C = 60 and R = 0. Substituting these values into the inequality, we get:

56(60) + 64(0) < 9000

3360 < 9000

This is true, so our assumption is valid.

Using the assumption that the airplane has enough fuel to fly for 1 hour in clear skies, we can solve for F and T:

T > F * C + 64R

T > F * 60 + 64(0)

T > 60F

Since we assumed the airplane has enough fuel to fly for 1 hour in clear skies, T must be greater than the amount of fuel consumed during that time:

T > F * 60

Combining these two inequalities, we get:

60F < T < 60F + 3360

Now we can choose any value of F between 0 and 64 that satisfies the inequality, and choose a value of T that is greater than 3360 + 60F. For example, we can choose:

F = 30 (assuming a fuel consumption rate of 30 gallons per minute in clear skies)

T = 4000 gallons (initial amount of fuel)

Substituting these values into the inequality, we get:

56C + 64R < 9000

56(60) + 64R < 9000

3360 + 64R < 9000

64R < 5640

R < 88.125

Therefore, the airplane can fly for 88.125 minutes (or approximately 1 hour and 28 minutes) through rain clouds before consuming all of its fuel, if it is flying at a rate of 64 gallons per minute. And if the airplane consumes fuel at a rate of 30 gallons per minute while flying through clear skies, it has 4000 gallons of fuel before takeoff

User Arad
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Explanation:

The coefficient of C in the inequality 56C+64R<9000 represents the rate of fuel consumption while flying through clear skies. From the inequality, we can see that the rate of fuel consumption while flying through clear skies is 56 gallons per minute.

To find the initial fuel capacity of the airplane, we need to set the values of C and R to zero in the inequality 56C+64R<9000, since this represents the scenario where the plane flies entirely through clear skies and does not encounter any rain clouds.

56(0) + 64(0) < 9000

Simplifying the inequality, we get:

0 < 9000

This means that the inequality is true for any positive value of C and R, including C = 0 and R = 0. Therefore, the airplane has more than 0 gallons of fuel before takeoff, but the exact amount is not specified in the given information.

User Setrofim
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