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Gelneren [198K]
3 years ago
14

12. What is the probability that a point in the square below

Mathematics
1 answer:
andrew-mc [135]3 years ago
8 0

Answer:

21.5\%

Step-by-step explanation:

we know that

The probability that a point in the square below  is in the shaded region, is equal to divide the area of the shaded region by the area of the square

step 1

Find the area of the shaded region

The area is equal to the area of the square minus the area of the circle

A=b^{2} -\pi(r)^{2}

we have

b=12\ cm ---> length side of the square

r=12/2=6\ cm ----> the radius is half the diameter

assume

\pi =3.14

substitute

A=12^{2} -(3.14)(6)^{2}

A=30.96\ cm^{2}

step 2

Find the area of the square

A=b^{2}

we have

b=12\ cm ---> length side of the square

substitute

A=12^{2}=144\ cm^{2}

step 3

Find the probability

P=30.96/144=0.215

Convert to percent form

0.215*100=21.5\%

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Answer:

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A(t)=100-80e^{-0.02t}

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(c) When t approaches to +infinit, the term e^(-0.02t) approaches to zero, so the amount of salt in the solution approaches to 100 lb.

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