Answer:
a) P(Y > 76) = 0.0122
b) i) P(both of them will be more than 76 inches tall) = 0.00015
ii) P(Y > 76) = 0.0007
Step-by-step explanation:
Given - The heights of men in a certain population follow a normal distribution with mean 69.7 inches and standard deviation 2.8 inches.
To find - (a) If a man is chosen at random from the population, find
the probability that he will be more than 76 inches tall.
(b) If two men are chosen at random from the population, find
the probability that
(i) both of them will be more than 76 inches tall;
(ii) their mean height will be more than 76 inches.
Proof -
a)
P(Y > 76) = P(Y - mean > 76 - mean)
= P(
) >
)
= P(Z >
)
= P(Z >
)
= P(Z > 2.25)
= 1 - P(Z ≤ 2.25)
= 0.0122
⇒P(Y > 76) = 0.0122
b)
(i)
P(both of them will be more than 76 inches tall) = (0.0122)²
= 0.00015
⇒P(both of them will be more than 76 inches tall) = 0.00015
(ii)
Given that,
Mean = 69.7,
= 1.979899,
Now,
P(Y > 76) = P(Y - mean > 76 - mean)
= P(
)) >
)
= P(Z >
)
= P(Z >
))
= P(Z > 3.182)
= 1 - P(Z ≤ 3.182)
= 0.0007
⇒P(Y > 76) = 0.0007
Price of boots is represented as x, price of tennis shoes is represented as y.
x-y=44.38
x+y=196.12
Isolate x. (Or y, if you wanted to)
x=y+44.38
x=196.12-y
Set them equal to each other.
y+44.38=196.12-y
Solve for y. Then plug it in to either of the two original equations to find x.
x=120.24
y=75.86
Note: This is assuming that the boots are more expensive than the tennis shoes. If the tennis shoes are more expensive than the boots, then the prices would be switched. I didn't find this clear in your question.
Answer:
2
Step-by-step explanation:
Using the distance formula,

We just need to plug in the numbers.
So 
Then we simplify it to

Finally, we get
, which is
when simplified.
if x equals 100 then the answer will be 100 because if you multiply 100 by 3 you will get 300