For this case we have to:
n: Represents the weight of Mary in Kg.
If your sister weighs 15 kg less we have:
Where "y" represents the weight of his sister in kg.
To find how many times Mary is heavier than her sister, we must divide Mary's weight by her sister's weight.
We have then:
Answer:
Mary is times heavier than her sister.
A) the probability is 0.123 or 12.3%.
B) the probability is 0.8589 or 85.89%.
C) the normal distribution can be used even though the sample is small because the population the sample is taken from is normally distributed.
ExplanationA) We first find the z-score that corresponds with this value.
Using a z-table (http://www.z-table.com) we find 1.16; this corresponds to a probability of 0.8770. However, This is the probability that a number will be lower than this; since we want the probability that the value is higher, we subtract from 1:
1-0.8770 = 0.123.
B) To find the probability of a sample mean, we use the formula
Looking in our z-table we see that this corresponds with 0.1611. Again, however, this is the area left of this value, which is the probability below; we want the probability above, so we subtract from 1:
1-0.1611 = 0.8589
2.73 is 439.5 divided by 161 rounded to the nearest hundredth
The equation of the height as a function of time for this case is given by:
h (t) = - 16t ^ 2 + 10t + 100
By the time the egg hits the ground we have:
-16t ^ 2 + 10t + 100 = 0
We look for the roots of the polynomial:
t1 = -2.2069555463432966
t2 = 2.8319555463432966
As it is about time, we use the positive root:
t = 2.83 s
Answer:
it hits the ground at:
t = 2.83 s
