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3 years ago

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A person travels 8 miles down a stream. In the same time they can travel 6 miles upstream. If the current of the river is 2 mph

what is the rate of the still boat?

1 answer:

e-lub [12.9K]3 years ago

5 0

Answer: the speed of the still boat is 14 mph

Step-by-step explanation:

Let x represent the speed of the still boat.

A person travels 8 miles down a stream. Assuming he travels with the current and if the current of the river is 2 mph, it means that the total speed is (x + 2) mph

Time = distance/time

Time spent in travelling with the current is

8/(x + 2)

In the same time they can travel 6 miles upstream. Assuming he travels against the current, it means that the total speed is (x - 2) mph

Time = distance/time

Time spent in travelling against the current is

6/(x - 2) .since the time is the same, then

8/(x + 2) = 6/(x - 2)

Cross multiplying, it becomes

8(x - 2) = 6(x + 2)

8x - 16 = 6x + 12

8x - 6x = 12 + 16

2x = 28

x = 28/2

x = 14

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Glen Davis is shooting free throws. Making or missing free throws doesn't change the probability that he will make his next one,

Serjik [45]

Answer:

0.00457 or 0.457%

Step-by-step explanation:

Glen Davis makes a free throw 74% of the time, meaning he misses 26% of the time. Four him to miss four in a row, it would require him to miss his first throw and his second throw and his third throw and his fourth throw. I highlight and because it is a helpful tip to remember that AND situations require multiplication while OR situations require addition.

So in this question we multiply the probabilities of him missing.

$P(MMMM) = \frac{26}{100}* \frac{26}{100} *\frac{26}{100}* \frac{26}{100} = 0.00457$

This answer has been rounded off to three significant figures

4 0

3 years ago

Read 2 more answers

The following table shows the estimated populations and annual growth rates for four countries in the year 2000. Find the

gladu [14]

Answer:

Part 1) Australia $19,751,012\ people$

Part 2) China $1,319,645,764\ people$

Part 3) Mexico $109,712,539\ people$

Part 4) Zaire $60,534,681\ people$

Step-by-step explanation:

we know that

The equation of a exponential growth function is given by

$P(t)=a(1+r)^t$

where

P(t) is the population

t is the number of years since year 2000

a is he initial value

r is the rate of change

Part 1) Australia

we have

$a=19,169,000\\r=0.6\%=0.6\100=0.006$

substitute

$P(t)=19,169,000(1+0.006)^t$

$P(t)=19,169,000(1.006)^t$

Find the expected population in 2025,

Find the value of t

t=2005-2000=5 years

substitute the value of t in the equation

$P(5)=19,169,000(1.006)^5=19,751,012\ people$

Part 2) China

we have

$a=1,261,832,000\\r=0.9\%=0.9\100=0.009$

substitute

$P(t)=1,261,832,000(1+0.009)^t$

$P(t)=1,261,832,000(1.009)^t$

Find the expected population in 2025,

Find the value of t

t=2005-2000=5 years

substitute the value of t in the equation

$P(5)=1,261,832,000(1.009)^5=1,319,645,764\ people$

Part 3) Mexico

we have

$a=100,350,000\\r=1.8\%=1.8\100=0.018$

substitute

$P(t)=100,350,000(1+0.018)^t$

$P(t)=100,350,000(1.018)^t$

Find the expected population in 2025,

Find the value of t

t=2005-2000=5 years

substitute the value of t in the equation

$P(5)=100,350,000(1.018)^5=109,712,539\ people$

Part 4) Zaire

we have

$a=51,965,000\\r=3.1\%=3.1\100=0.031$

substitute

$P(t)=51,965,000(1+0.031)^t$

$P(t)=51,965,000(1.031)^t$

Find the expected population in 2025,

Find the value of t

t=2005-2000=5 years

substitute the value of t in the equation

$P(5)=51,965,000(1.031)^5=60,534,681\ people$

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2 years ago

What is 44 hundereths in it's simplest form?

Serga [27]

22/25 i believe... i hope this helps

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2 years ago

What is the price if it’s 20% off $30

Xelga [282]

Answer: $24

Step-by-step explanation:

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2 years ago

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NeX [460]

Answer:

C. Wright Mills

Step-by-step explanation:

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2 years ago