Answer:
a. 0.38%
b. 266.75 days
Step-by-step explanation:
We have the following data, mean (m) 269 and standard deviation (sd) 15, therefore:
a. The first thing is to calculate the number z:
z (x) = (x - m) / sd
z (309) = (309-269) / 15 = 2.67
When looking in the normal distribution table (attached), we have that at this value of z, the probability is:
P (z> 2.67), that is to say we must look in the table -2.67 and this value corresponds to 0.0038, that is to say 0.38%
b. Find the z-value with a left tail of 44%, i.e. 0.44. We look in the table for this value and what value of z corresponds.
invNorm (0.44) = -0.15
Find the corresponding number of days:
x = z * sd + m
we replace
d = -0.15 * 15 + 269 = 266.75 days
K=4
add seven on both sides
2x-4y=7
add 4y on both sides
2x=7+4y
divide 2 on both sides
x=7+4y/2
plug that into original equation
2(7+4y/2)-4y-7=0
7 and 4y cancel out
2(2)=0
4=0
-3, 3, 5.
https://www.wolframalpha.com/input/?i=%28x%5E3%29-%285x%5E2%29-9x%2B45%3D0
Answer:
x=-8
Step-by-step explanation:
I always change the decimals into whole numbers by multiplying them by 10. If you do this, it is much easier to solve. All you do is multiply every term by 10.
the equation changes to
-5(x+3)-2x=41
-5x-15-2x=41
combine like terms
-7x-15=41
bring the 15 over to the 41
-7x=56
divide everything by 7
-x=8
change x to a positive
x=-8
For the first one write 9 divided by 2 gives your your radius an it’s 3.5. the formula is 2 x 3.14 x radius and that gives you 21.98.
the 2nd one is 2 x 3.14 x 9 = 56.52
the 3rd is 2 x 3.14 x 5= 31.4
formula is always 2 x 3.14 (or pie) x radius
to get your radius from your diameter you do your diameter divided by 2