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Comment on Hummingbird Feeder
From where you got 0.75?
We're told that the volume
We're told that the volume decreases by 25%, In other words, it decreases by 1/4
Another way to look at it is to say that 3/4 of the volume remains. So, to find the next volume, we multiply by 3/4
For example, let's start with 8 liters.
One approach is to subtract 1/4 of 8
(1/4)(8) = 2
We get: 8 - 2 = 6
Alternatively, 3/4 of 8 = (3/4)(8) = 6
Same answer either way. HOWEVER, the second one if more convenient/faster
I solved this question using
as 81/16 = 5.0625 therefore, generating tale
Time : liquid
12 hours from now 5.0625
6 hours from now .75 x A = 5.065 => A= 6.75
Now ( current time) .75 x B = 6.75 => B = 9
6 hours ago .75 x C = 9 => C = 12
therefore answer is 12
A is liquid at time 6 hours from now
B is liquid right now
C is liquid 6 hours ago
That works too - well done!
That works too - well done!
Took a little practice, but
Good stuff!!
Good stuff!!
Instead of starting with 6
1) start with Now = P
2) find P = 81/16=P(.75)^2...then
3) P(1.25) = 6 hours ago?
I wouldn't intuitively think to begin with 6 hours ago being P.
Your solution is perfectly
Your solution is perfectly valid.
The advantage with letting P = volume 6 hours ago is that, once we solve the equation for P, we have our answer.
That said, your approach works just as well.
Cheers,
Brent
Test the answers will work,