Answer: 
This is the same as writing y = 650(0.907)^t
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Explanation:
Exponential equations can be of the form y = a*b^t
- a = initial amount
- b = growth or decay factor
In this case, we have
- a = 650 mg to start with
- b = 1 - 0.093 = 0.907 as the decay factor
If we had exponential growth, then we'd compute 1 + 0.093 instead.
Based on those values, we go from y = a*b^t to y = 650(0.907)^t which is the same as writing 
Other exponential forms are possible, but I think this form is the most intuitive. The 0.907 means that 90.7% of the sample remains after each year.
Answer: 36 sec
Step-by-step explanation:
Let
x------> distance the kitten runs before being caught by the puppy
Remember that
The speed is equal to divide the distance by the time
v=d/t
solve for t
t=d/v
so
equate the time
x/20=(180+x)/25
25x=20(180+x)
25x=3,600+20x
25x-20x=3,600
x=3,600/5=720 m
t=d/v=720/20=36 sec
or
t=(720+180)/25=900/25=36 sec
Answer:
The wife gets £468 over the son
Step-by-step explanation:
Firstly, we shall calculate the total amount Brian made from from what he and Paul won.
The ratio is 1:4, meaning for every 2 part Brain takes, Paul takes 4
Paul’s share is thus 1/5 * 7800 = 7800/5 = £1560
Now we have another ratio for sharing the amount Brain has at home.
The total ratio here is 1+6+3 = 10
The share of the wife will be 6/10 * 1560 = 6 * 156 = 936
The son share is half of this which is 936/2 = 468
The difference between their shares is £936-£468 = £468
Answer:
10x+3y+2
Step-by-step explanation: