Answer is 18 due to the theory cause
The first term (a) is - 18
You add 5 to get to the next term. Or you can solve it by taking any 2 consecutive terms and find their difference.
Formula
d = t4- t3
Givens
t4 = - 3
t3 = - 8
Solution 1
d = t4 - t3 Substitute
d = -3 - ( - 8) Remove the brackets
d = -3 + 8 Combine
d = 5 Difference
Remark
Find the general formula
tn = - a + (n - 1)d Substitute
So term 20 = Example
t20 = -18 + (20 - 1)*5 Combine the inside of the brackets. Remove the brackets
t20 = - 18 + 19*5 Combine 19 and 5
t20 = -18 + 95 "Subtract"
t20 = 77 Answer
When you have this type of problem, you need to combine the like-terms and isolate the variable.
3x + 122 = 22x - 11
Add 11 to both sides to get rid of it
3x + 122 + 11 = 22x - 11 + 11 (-11 + 11=0)
3x + 133 = 22x
Then you would bring the 3x to the other side, so subtract 3x from both sides
3x + 133 = 22x
-3x -3x
133 = 22x - 3x
133 = 19x
Then divide both sides by 19 to isolate x
133/19 = 19x/19
133/19 = 7, so x = 7
Hope this helps!!
Answer:
% Remaining![= [1-(1/2)^{\frac{t}{2.6}}]x100](https://tex.z-dn.net/?f=%20%3D%20%5B1-%281%2F2%29%5E%7B%5Cfrac%7Bt%7D%7B2.6%7D%7D%5Dx100%20)
And replacing the value t =5.5 hours we got:
% Remaining![= [1-(1/2)^{\frac{5.5}{2.6}}]x100 =76.922\%](https://tex.z-dn.net/?f=%20%3D%20%5B1-%281%2F2%29%5E%7B%5Cfrac%7B5.5%7D%7B2.6%7D%7D%5Dx100%20%3D76.922%5C%25)
Step-by-step explanation:
Previous concepts
The half-life is defined "as the amount of time it takes a given quantity to decrease to half of its initial value. The term is most commonly used in relation to atoms undergoing radioactive decay, but can be used to describe other types of decay, whether exponential or not".
Solution to the problem
The half life model is given by the following expression:

Where A(t) represent the amount after t hours.
represent the initial amount
t the number of hours
h=2.6 hours the half life
And we want to estimate the % after 5.5 hours. On this case we can begin finding the amount after 5.5 hours like this:

Now in order to find the percentage relative to the initial amount w can use the definition of relative change like this:
% Remaining = 
We can take common factor
and we got:
% Remaining![= [1-(1/2)^{\frac{t}{2.6}}]x100](https://tex.z-dn.net/?f=%20%3D%20%5B1-%281%2F2%29%5E%7B%5Cfrac%7Bt%7D%7B2.6%7D%7D%5Dx100%20)
And replacing the value t =5.5 hours we got:
% Remaining ![= [1-(1/2)^{\frac{5.5}{2.6}}]x100 =76.922\%](https://tex.z-dn.net/?f=%3D%20%5B1-%281%2F2%29%5E%7B%5Cfrac%7B5.5%7D%7B2.6%7D%7D%5Dx100%20%3D76.922%5C%25)
your answer is -1/100 (a fraction)