If a rock falls from a height of 40 meters on Earth, the height H (in meters) after x seconds is approximately

1 answer:

4 0

Once the rock hits the ground, we know that its height will be equal to 0m
because of this, we can replace H(x) with 0
$40 - 4.9 {x}^{2} = 0$
now all we have to do is get x by itself
so..
$4.9 {x}^{2} = 40$
then
${x}^{2} = 40 \div 4.9$
${x}^{2} = 8.1632...$
now take the square root of each side
$x = 2.857...$
2.857 seconds (rounded to the third decimal)

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In a reliability test there is a 42% probability that a computer chip survives more than 500 temperature cycles. If a computer c

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Answer:

The probability is $P(B' n A ' ) =$ 16%

Step-by-step explanation:

From the question we are told that

A is the event that the chip was "made by company A"

B is the event that a chip "survives 500 temperature cycles"

The probability that a computer chip survives more than 500 temperature cycles is

$P(B) = 42$ % $= 0.42$

The probability that does not survive more than 500 temperature cycles and it was manufactured by company A is $P(A | B' ) = 0.73$

The probability that the computer chip is not manufactured by company A and does not survive more than 500 temperature cycles is mathematically evaluated as

$P(B' n A ' ) = P (B' | A' ) P(B ')$