12 total letters...5 vowels and 7 consonants.
probability of 1st letter being a vowel is 5/12
after replacing ...
probability of 2nd letter being a vowel is 5/12
probability of both occurring is (5/12 * 5/12) = 25/144 <===
Answer:
D) 2x² + 4x - 30
Step-by-step explanation:
Follow the FOIL method:
FOIL =
First
Outside
Inside
Last
...and is the order you multiply to solve:
(x + 5)(2x - 6) =
(x)(2x) = 2x²
(x)(-6) = -6x
(5)(2x) = 10x
(5)(-6) = -30
Combine like terms. Simplify:
2x² -6x + 10x - 30 = 2x² (-6x + 10x) - 30 = 2x² + 4x - 30
2x² + 4x - 30 is your answer.
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Given that the concentration has been modeled by the formula:
C(t)=50t/(t^2+25)
where:
t is time in hours.
The concentration after 5 hours will be given by:
t= 5 hours
plugging the value in the equation we get:
C(5)=(50(5))/(5^2+25)
simplifying the above we get:
C(5)=250/(50)=5 mg/dl
Answer: 5 mg/dl