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3 years ago

There are currently 73 million cars in a certain country, decreasing by 1.7% annually.

Mathematics

1 answer:

Olin [163]3 years ago

7 0

Answer:

17.6 years

Step-by-step explanation:

There are currently 73 million cars in a certain country, decreasing by 1.7% annually.

How many years will it take for this country to have 54 million cars? Round to the

nearest year.

We use the formula

y = a(1 - r)^t

a = Initial amount = 73 million cars

y = Future amount = 54 million cars

r = decreasing rate = 1.7 % = 0.017

t = time is unknown

54,000,000 = 73,000,000(1 - 0.017)^t

Divide both sides by 73,000,000

54,000,000/73,000,000 = (0.983)^t

0.7397260274 = (0.983)^t

Take the logarithm of both sides

log 0.7397260274 = Log (0.983)^t

log 0.7397260274 =t log (0.983)

t = log 0.7397260274/log 0.983

t = -0.13092910029/-0.00744648216

t = 17.5826783005 years

Approximately = t = 17.6 years

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Answer:

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2 years ago

the radius of a sheridan balloon is increasing at a rate of 3 centimeters per minute. how fast is the volume changing when the r

san4es73 [151]

The volume of the balloon is $2352\pi cc/min$

Explanation:

The radius of the balloon is increasing at a rate of 3 cm/min.

To determine the volume of the balloon when the radius is 14 cm, we shall use the formula $V=\frac{4}{3} \pi r^3$

The rate of change of r with respect to time t is given by,

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Now, we shall determine the $\frac{d}{d t}(V)$

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3 years ago

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dusya [7]

Answer:

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Step-by-step explanation:

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2 years ago

Read 2 more answers

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Alexus [3.1K]

Answer:

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Step-by-step explanation:

We are given x=- 3 , y= 6 and z= -4.

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Substitute -3 in for x and 6 in for y.

-15 + (- -3) + 6

2 negative signs creates a positive sign

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Add -15 and 3.

(-15+3) +6

-12 +6

Add -12 and 6.

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