Answer: number of years that it will take for the balance to reach $120,000 is 42 years
Step-by-step explanation:
Initial amount deposited into the account is $4000. This means that the principal is $4000
P = 4000
It was compounded annually. This means that it was compounded once in a year. So
n = 1
The rate at which the principal was compounded is 8.4%. So
r = 8.4/100 = 0.084
Let the number of years that it will take for the balance to reach $120,000. It means that it was compounded for a total of t years.
Amount, A at the end of t years is $120,000
The formula for compound interest is
A = P(1+r/n)^nt
120000 = 4000(1 + 0.084/1)^1×t
120000/4000 = 1.084^t
30 = 1.084^t
t = 42 years
Answer:
- P(t) = 100·2.3^t
- 529 after 2 hours
- 441 per hour, rate of growth at 2 hours
- 5.5 hours to reach 10,000
Step-by-step explanation:
It often works well to write an exponential expression as ...
value = (initial value)×(growth factor)^(t/(growth period))
(a) Here, the growth factor for the bacteria is given as 230/100 = 2.3 in a period of 1 hour. The initial number is 100, so we can write the pupulation function as ...
P(t) = 100·2.3^t
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(b) P(2) = 100·2.3^2 = 529 . . . number after 2 hours
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(c) P'(t) = ln(2.3)P(t) ≈ 83.2909·2.3^t
P'(2) = 83.2909·2.3^2 ≈ 441 . . . bacteria per hour
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(d) We want to find t such that ...
P(t) = 10000
100·2.3^t = 10000 . . . substitute for P(t)
2.3^t = 100 . . . . . . . . divide by 100
t·log(2.3) = log(100)
t = 2/log(2.3) ≈ 5.5 . . . hours until the population reaches 10,000
Answer:
Yes, they vary directly
Step-by-step explanation:
y=kx; k is the constant (12 in this case) and as x increases y increases, so they vary directly
Answer:
1. 15x^7y^2 + 4x^3 => x^3(15x^4y^2 + 4)
2. 15x^7y^2 + 3x => 3x(5x^6y^2 + 1)
3. 15x^7y^2 + 6xy => 3xy(5x^6y + 2)
4. 15x^7 + 10y^2 => 5(3x^7 + 2y^2)
Step-by-step explanation:
To obtain the answer to the question, first let us factorise each expression. This is illustrated below:
1. 15x^7y^2 + 4x^3
Common factor is x^3, therefore the expression is written as:
x^3(15x^4y^2 + 4)
2. 15x^7y^2 + 3x
Common factor is 3x, therefore the expression is written as:
3x(5x^6y^2 + 1)
3. 15x^7y^2 + 6xy
Common factor is 3xy, therefore the expression is written as:
3xy(5x^6y + 2)
4. 15x^7 + 10y^2
Common factor is 5, therefore the expression can be written as:
5(3x^7 + 2y^2)
Answer:
Step-by-step explanation:
<u>Area of the larger circle:</u>
<u>The shaded area:</u>
- π(2r)² - πr² = 75
- 3πr² = 75
- πr² = 25
<u>Area of the larger circle:</u>
