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3 years ago

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If the moon is directly over the beanstalk, how many days after the beanstalk was planted would the beanstalk reach the moon? (T

he moon is 238,900 miles from the earth, and there are 5,280 feet in 1 mile.)

1 answer:

olchik [2.2K]3 years ago

3 0

Answer:

28.23 days

Explanation:

Length of magic beanstalk=4 feet

Height increasing exponentially and double each day.

We have formula

$y=a(b)^t$

Where t=Time (in day)

We have a=4

When t=1 then y=8

$8=4b^1$

$b=\frac{8}{4}=2$

$b=2$

Distance between moon and earth=y=238,900 miles= $238900\times 5280 feet$

Substitute the values

$238900\times 5280=4(2)^t$

$\frac{238900\times 5280}{4}=2^t$

$315348000=2^t$

$ln(315348000)=tln 2$

$t=\frac{ln315348000}{ln 2}$

$t=28.23 days$

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Explanation :

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