Answer:
A) 68.33%
B) (234, 298)
Step-by-step explanation:
We have that the mean is 266 days (m) and the standard deviation is 16 days (sd), so we are asked:
A. P (250 x < 282)
P ((x1 - m) / sd < x < (x2 - m) / sd)
P ((250 - 266) / 16 < x < (282 - 266) / 16)
P (- 1 < z < 1)
P (z < 1) - P (-1 < z)
If we look in the normal distribution table we have to:
P (-1 < z) = 0.1587
P (z < 1) = 0.8413
replacing
0.8413 - 0.1587 = 0.6833
The percentage of pregnancies last between 250 and 282 days is 68.33%
B. We apply the experimental formula of 68-95-99.7
For middle 95% it is:
(m - 2 * sd, m + 2 * sd)
Thus,
m - 2 * sd <x <m + 2 * sd
we replace
266 - 2 * 16 <x <266 + 2 * 16
234 <x <298
That is, the interval would be (234, 298)
Answer:
53.57%
Step-by-step explanation:
We have to calculate first the specific number of events that interest us, if at least 3 are girls, they mean that 2 are boys, therefore we must find the combinations of 3 girls of 5 and 2 boys of 3, and multiply that, so :
# of ways to succeed = 5C3 * 3C2 = 5! / (3! * (5-3)!) * 3! / (2! * (3-2)!)
= 10 * 3 = 30
That is, there are 30 favorable cases, now we must calculate the total number of options, which would be the combination of 5 people from the group of 8.
# of random groups of 5 = 8C5 = 8! / (5! * (8-5)!) = 56
That is to say, in total there are 56 ways, the probability would be the quotient of these two numbers like this:
P (3 girls and 2 boys) = 30/56 = 0.5357
Which means that the probability is 53.57%
You would fill in 9 for x so your equation would be 2(9)+3 and you would then get 21. Therefore the answer is f(x)=21
Answer:
A=1, B=3, C=15
Step-by-step explanation:
I think that
1(3x+3)=15
3x+3=15
3x=12
x=4
I hope this helps you
10^2=5^2+x^2
100-25= x^2
x= 5 square root of 3
