The square root of pi is 1.77245385091
Answer:
3.14
Step-by-step explanation:
Given that:
Mean weight (m) = 79 ounces
Population standard deviation (s) = 13.1
Sample size = 47
Maximal margin of error associated with 90% confidence interval.
The margin of error is given by:
Zcritical * (standard deviation / sqrt(sample size)
Z critical at 90% confidence interval = 1.645
Hence,
Zcritical * (standard deviation / sqrt(sample size)
1.645 * 13.1 / sqrt(47)
1.645 * (13.1 / 6.8556546)
1.645 * 1.9108313
Hence, the margin of error is :
3.1433174885
= 3.14
If you expand out the brackets you get this,
(4+5i)(a+2i) = 4a + (5a)i + 8i - 10
The -10 comes from 5i * 2i.
Squaring i becomes -1.
Let's group the real stuff together,
and imaginary separately,
(4a - 10) + (5a + 8)i
For this to be purely imaginary,
the real part needs to be zero.
Therefore 4a - 10 = 0
Solve for a.
x + y = 24 where x and y are the 2 parts of diagonal Other diagonal wil be smaller that 24.
x^2 + z^2 = 13^2
y^2 + z^2 = 20^2 where z = 0.5 * length of smaller diagonal)
form last 2 equations
y^2 - x^2 = 20^2 - 13^2 = 231
now y = 24-x so we have
(24 - x)^2 - x^2 = 231
576 - 48x = 231
48x = 345
x = 7.1875
z^2 = 13^2 - 7.1875^2 = 117.34
z = 1.83
so smaller diagonal = 21.66 cm
looks like its the third choice.
Answer:
Since the equation is addition, reverse it into subtraction. 210-53.715-51.3-52.62= 52.365. You can add 53.715 by 51.3 by 52.62 by 52.365 to check your answer, and it will be 210 so the 4th runner ran 52.365 seconds.
i also got this question but i figured it out lol
