= -3/2 * -5 1/4
convert 5 1/4 to improper fraction
= -3/2 * -21/4
multiply numerators; multiply denominators
= (-3*-21)/(2*4)
multiply in parentheses
= 63/8
convert back to mixed number
= 7 7/8
ANSWER: Since the exact answer is the mixed number 7 7/8, a reasonable estimate is 8.
Hope this helps! :)
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!
There are 651.335 million cells in the petri dish after 11 hours and the cells will reach 1 billion cells after 14.068 hours
<h3>How to determine the number of cells after 11 hours?</h3>
The given parameters are:
At t = 0, Bacteria = 140 million
At t = 6, Bacteria = 320 million
This can be represented as:
f(0) = 140
f(6) = 320
An exponential function is represented as:
f(t) = f(0) * r^t
When t = 6, we have:
320 = 140 * r^6
Divide both sides by 140
r^6 = 2.28571428571
Take the 6th root of both sides
r = 1.15
So, we have:
f(t) = f(0) * 1.15^t
Substitute f(0) = 140
f(t) = 140 * 1.15^t
After 11 hours, we have:
f(11) = 140 * 1.15^11
Evaluate
f(11) = 651.33
Hence, there are 651.335 million cells in the petri dish after 11 hours
Time to reach 1 billion cells
This means that
f(t) = 1 billion i.e. 1000 million
So, we have:
1000 = 140 * 1.15^t
Divide by 140
1.15^t = 7.14285714286
Take the logarithm of both sides
t * log(1.15) = log(7.14285714286)
Divide both sides by log(1.15)
t = 14.068
Hence, the cells will reach 1 billion cells after 14.068 hours
Read more about exponential functions at:
brainly.com/question/2456547
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Simplifying it would make it 3/4b^2. I can't write it down the correct way, but it's three over four times b squared. Unless it's a square root, then things would be different.
Answer:
*answerness*
Step-by-step explanation:
*answerness*