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!
B. 6 3/8
How do we get this? Simple:
6.375--->We already know that 6 will be the whole number in the mixed fraction.
We then move on to represent the decimal part as the fraction. 375 will be the numerator. The denominator depends on how many decimal places we have (3 in this case, since there are 3 numbers after the period--375). Each decimal place represents a 10 (or a 0 after the 1). So we get that our denominator will be a 1000.
We get the following fraction
6 375/1000
We simplify. Let's start by dividing numerator and denominator by 5:
6 75/200
Let's divide by 5 again:
6 15/40
Let's divide by 5 again:
6 3/8
Or we could have divide by 125 from the get go and get the same results.
Answer:
3053.63 cm^3
Step-by-step explanation:
Volumme of a sphere = 
We do not have the radius of the sphere, but we have its diameter.
We know that there is a relationship between radius and diameter.
Then the formula of the volume of a sphere according to its diameter is:
