Answer:
Rate of Decay = 8%
Step-by-step explanation:
The decay formula is:

Where F is the final value (here, it is given as "Y")
P is the initial value (here, given as 20,000)
r is the rate of decay (what we need to find)
t is the time (given as 2)
Comparing both the equations:

We see that:
1 - r =0.92
We solve for "r":
1 - 0.92 = r
0.08 = r
The rate of decay is 0.08, as a percentage, we need to multiply by 100, so we have:
0.08 * 100 = 8%
Rate of Decay = 8%
Answer:
C
Step-by-step explanation:
I got the answer C because if the estimated value of the tank is 50 and it gets drained it will only have 18 gallon in it
Answer:
1 hour and 15 minutes thats how long the documentary was
Answer:
48 minutes
Step-by-step explanation:
Given that:
Time taken by Janet = 3 hours
Janet's rate = 1/3 job / hour
Time taken by Garry = 2 hours
Garry's rate = 1/2
Rate of working together :
1/3 + 1/2 = (2 + 3) /6 = 5/6 job/hour
If Janet works for one hour before Garry joins ;
1/3 of the job has been done by Janet
1 - 1/3 = 2/3 of the job left
Hence to finish the job together, it will take :
Fraction of JOB left ÷ rate of working together
(2/3 ÷ 5/6)
= 2 /3 * 6/5
= 12 / 15
= 4 / 5 hours
To minutes
(4/5) * 60
= 240/5
= 48 minutes
Andrew has 10 pens bc it's half of twenty