All categories

4 years ago

10.

Mathematics

2 answers:

Crank4 years ago

5 0

7.5 × 10-4

That's the scientific notation answer ^

Nesterboy [21]4 years ago

4 0

The answer for this question is 7.5 times 10 -4

You might be interested in

Posting a screenshot, help pls.

Nikolay [14]

When h=0, that is when it hits the ground

0=70-4t-16t²
based on your previous questions, you should have learned how to complete the square

solve by copmleting the square

minus 70 both sides
-70=-4t-16t²
times both sides by -1
70=4t+16t²
16t²+4t=70
divide both sides by 16
t²+1/4t=35/8
take 1/2 of the linear coefint and square it
half of 1/4=1/8, (1/8)²=1/64
add that to both sides
t²+1/4t+1/64=35/8+1/64
factor perfect square trionomial
$(t+\frac{1}{8})^2=\frac{35}{8}+\frac{1}{64}$
$(t+\frac{1}{8})^2=\frac{280}{64}+\frac{1}{64}$
$(t+\frac{1}{8})^2=\frac{281}{64}$
square root both sides, remember to take positive and negative roots
$t+\frac{1}{8}=\frac{+/-\sqrt{281}}{8}$
minus 1/8
$t=\frac{-1+/-\sqrt{281}}{8}$

$t=\frac{-1+\sqrt{281}}{8}$ or $t=\frac{-1-\sqrt{281}}{8}$
the 2nd solution is not valid because that gives us a negative time, before the ball was dropped

so $t=\frac{-1+\sqrt{281}}{8}$ is the solution
t≈1.97

1.97 seconds

7 0

4 years ago

I need help with this math question pretty please

AleksAgata [21]

Just do 11x18x20x14 and u should get it

3 0

3 years ago

Read 2 more answers

What is the factored form of the following expressions?<br><br> d^2 + 2d – 48

Andreas93 [3]

Answer:

(d-6) (d+8)

Step-by-step explanation:

d^2 + 2d – 48

What two numbers multiply to -48 and add to 2

-6 * 8 = -48

-6+8 = 2

(d-6) (d+8)

4 0

3 years ago

Which expression is equivalent to-8x-1y-9/-15x5y-3?

Vladimir79 [104]

Answer:

Yuhh the answers c dawhggg trus me i just did the same thing lawl!

Step-by-step explanation:

4 0

3 years ago

2. The mean birth weight of a full term boy born in the US is 7.7 lbs, with standard deviation of 1.1 lbs. A. Find the probabili

Fed [463]

Answer:

The value is $P( X < 7 ) =0.26226$

The value is $P( X < 7 ) = 0.00073$

Step-by-step explanation:

From the question we are told that

The population mean is $\mu = 7.7 lbs$

The standard deviation is $\sigma = 1.1 \ lbs$

The sample size is n = 25

Generally the probability that a boy born full term in the US weighs less than 7 lbs is mathematically represented as

$P( X < 7 ) = P( \frac{X - \mu }{\sigma} < \frac{7 - 7.7 }{1.1 } )$

$\frac{X -\mu}{\sigma } = Z (The \ standardized \ value\ of \ X )$

=> $P( X < 7 ) = P(Z$

From the z table the area under the normal curve to the left corresponding to -0.6364 is

$P(Z$

=> $P( X < 7 ) =0.26226$

Generally the standard error of mean is mathematically represented as

$\sigma_{x} = \frac{\sigma }{\sqrt{n} }$

=> $\sigma_{x} = \frac{ 1.1 }{\sqrt{25} }$

=> $\sigma_{x} = 0.22$

Generally the probability that the average weight of 25 baby boys born in a particular hospital have an average weight less than 7 lbs is mathematically represented as

$P( \= X < 7 ) = P( \frac{\= X - \mu }{\sigma_{x}} < \frac{7 - 7.7 }{ 0.22 } )$

=> $P( X < 7 ) = P(Z$

From the z table the area under the normal curve to the left corresponding to -3.1818 is

=> $P(Z$

=> $P( X < 7 ) = 0.00073$

4 0

3 years ago