Answer:
The number of fringes at is given as 20.
Step-by-step explanation:
Question
A Galapagos cactus finch population increases by half every decade. The number of finches is modeled by the expression
,
where d is the number of decades after the population was measured. Evaluate the expression for d = −2
Given :
The number of finches is modeled by the expression :
⇒
where is the number of decades after the population was measured.
To evaluate the expression for d=-2
Solution:
In order to evaluate the given expression to find the number of finches at , we will plugin for in the expression and simplify it.
Plugging in in the expression:
⇒
Using negative exponent property. [
⇒
⇒
⇒ (Answer)
Thus, the number of fringes at is given as 20.
This means the number of fringes two decades ago was 20.
The answer would be 11 gallons.
The tub starts with 32 gallons. Every minute it loses 3 gallons.
So after 1 minute it has lost 3 gallons. For example:
32-3= 29 Meaning that after 1 minute the tub has 29 gallons left.
Now you have to remember that the tub is draining for 7 minutes. So it is losing 3 gallons 7 times, because it loses 3 gallons each minute and there are 7 minutes.
We can use multiplication to find how many gallons the tub loses after 7 minutes. This sign “X” basically means “groups of”. We have 7 groups of 3, or
7 X 3
This is the same as saying we have 3, 7 times. Written like this:
3+3 +3 +3 +3 +3 +3 = 21
So after 7 minutes the tub has lost 21 gallons.
Now we take the original number of gallons and take away what was lost:
32-21=11
So there are 11 gallons left after 7 minutes.
Please let me know if you need any further explanation. Hope this helped.
Answer:
Not 100% sure but i will say (B)
Step-by-step explanation:
Because it will be half2 standard deviation which will include 500-700.
2std will include from 300-700.
so it will be half of 95%.