Answer:
First one: 5x3(0.75)2t
and fourth one: 0.05x500(0.005)t
Step-by-step explanation:
In order to have an exponencial decay, the rate of the exponencial function needs to be lesser than 1.
The rate is the value between parenthesis, so in the first equation, the rate is 0.75, so this is an exponencial decay.
The second equation has rate = 2.4, so this is not an exponencial decay.
The third equation has rate = 1.04, so this is not an exponencial decay.
The fourth equation has rate = 0.005, so this is an exponencial decay.
Answer:
53.57%
Step-by-step explanation:
We have to calculate first the specific number of events that interest us, if at least 3 are girls, they mean that 2 are boys, therefore we must find the combinations of 3 girls of 5 and 2 boys of 3, and multiply that, so :
# of ways to succeed = 5C3 * 3C2 = 5! / (3! * (5-3)!) * 3! / (2! * (3-2)!)
= 10 * 3 = 30
That is, there are 30 favorable cases, now we must calculate the total number of options, which would be the combination of 5 people from the group of 8.
# of random groups of 5 = 8C5 = 8! / (5! * (8-5)!) = 56
That is to say, in total there are 56 ways, the probability would be the quotient of these two numbers like this:
P (3 girls and 2 boys) = 30/56 = 0.5357
Which means that the probability is 53.57%
(9x^4-13x^3-x-7)+(7x^3-2x+1)=
9x^4-13x^3-x-7+7x^3-2x+1=
9x^4+(-13+7)x^3+(-1-2)x-7+1=
9x^4+(-6)x^3+(-3)x-6=
9x^4-6x^3-3x-6
Answer: Option <span>D.)9x^4−6x^3−3x−6</span>