You would probably need a little larger sample of people because not all people wear corrective lenses. In almost any other survey, this would be a scientist’s dream, but in this one, you’d need it to be a little bigger.
Answer:
1/4
Step-by-step explanation:
Let's denote the probabilities as following:
Probability that a teenager has a sister:
P(A) = 12/28
Probability that a teenager has a brother:
P(B) = 7/28
Probability that a teenager has both a sister and a brother:
P(A⋂B) = 3/28
Probability that a selected teenager has a sister also has a brother, or in other words, he/she has a brother, given he/she had a sister:
P(B|A)
Let's apply the formula of conditional probability to work out P(B|A)
P(B|A) = P(A⋂B)/P(A) = (3/28)/(12/28) = (3*28)/(12*28) = 3/12 = 1/4
=> Option C is correct
Hope this helps!
Answer:
Step-by-step explanation:
It is given that,
The average distance between the Earth and the Moon is 384 400 km.
We need to express in in standard form.
1 km = 1000 m
It means,
384400 km = 384400000 km
or
=
Hence, the average distance between the Earth and the Moon is .
Step-by-step explanation:
with your square root symbol I never know what is inside the square root and what is possibly outside.
so, I can only guess and see what comes close.
f(x) = 2x² + x - 1
g(x) = sqrt(2x - 1) ??? is that so ?
h(x) = -2
2g(f(x)) + h(x)
g(f(x)) means that the whole f(x) expression is used as x in g(x).
the whole combined function is then
2×sqrt(2(2x² + x - 1) - 1) - 2
2×sqrt(4x² + 2x - 2 - 1) - 2
2×sqrt(4x² + 2x - 3) - 2
and if I am not mistaken, then this is the solution you mentioned at the beginning (if I try to read between the typos and missing info).
this is how people get to this.
do you understand it now ? or is there still something unclear ?
