Answer:
Left: The substance is decreasing by 1/2 every 12 years
Right: The substance is decreasing by 5.61% each year
Step-by-step explanation:
exponential decay
A = P(1-r)ᵇⁿ, where A is the final amount, P is the initial amount, r is the rate decreased each time period, b is the number of years, and n is the number of times compounded each year
let's write each formula in terms of this
left:
f(t) = 600(1/2)^(t/12)
matching values up...
A = P(1-r)ᵇⁿ
A = f(t)
P = 600
1 - r = 1/2 -> r = 1/2
t/12 = bn -> b = number of years = t, so bn = b/12 -> n = 1/12. Thus, it is compounded 1/12 times each year, so it is compounded every t*12 = 12 years. If it was compounded each month, it would be compounded 12 times a year
Thus, this is decreasing by a rate of 1/2 each 12 years
right:
f(t) = 600(1-0.0561)^(t)
matching values up...
A = P(1-r)ᵇⁿ
A = f(t)
P = 600
1 - r = 1 - 0.0561 -> r = 0.0561 = 5.61%
t = bn -> b = number of years = t, so bn = b -> n = 1. Thus, it is compounded annually (1 time each year)
Thus, this is decreasing by a rate of 5.61% each year
I am not sure, but I'll give you the layout.
Step-by-step explanation:
32/160= p/100
P=?
P stands for the percent
4,6,8 are being counted by twos so the next one is 10
4•3= 12, 6+3=9, 8-3=6, the next operation I assume would be division so 10/3= 3.34
No it is not proportional
Answer: 30 pounds of coffee beans worth $10.50 per pound was used.
20 pounds of coffee beans worth $13.00 per pound was used.
Step-by-step explanation:
Let x represent the number of coffee beans worth $10.50 per pound that should be mixed.
Let y represent the number of coffee beans worth $13.00 per pound that should be mixed.
50 pounds of beans worth $11.50 per pound is to be made. The total cost of the mixture would be
50 × 11.5 = 575
This means that
10.5x + 13y = 575 - - - - - - - 1
The total number of pounds of each type of coffee used is 50. This means that
x + y = 50
Substituting x = 50 - y into equation 1, it becomes.
10.5(50 - y) + 13y = 575
525 - 10.5y + 13y = 575
- 10.5y + 13y = 575 - 525
2.5y = 50
y = 50/2.5 = 20
x = 50 - 20= 30