Answer:

Step-by-step explanation:
The standard compound interest formula is given by:

Where A is the amount afterwards, P is the principal, r is the rate, n is the times compounded per year, and t is the number of years.
Since we are compounding annually, n=1. Therefore:

Lester wants to invest $10,000. So, P=10,000.
He wants to earn $1000 interest. Therefore, our final amount should be 11000. So, A=11000.
And our timeframe is 3.3 years. So, t=3.3. Substituting these values, we get:

Let’s solve for our rate r.
Divide both sides by 10000:

We can raise both sides to 1/3.3. So:

The right side will cancel:

So:

Use a calculator:

So, the annual rate of interest needs to be about 0.03 or 3% in order for Lester to earn his interest.
Answer:
C). 0.39 grams
Step-by-step explanation:
First find how many half-lifes are in 3 hours:
3 hours ÷ 20 minutes = 9 half-lifes
Find the total left:
0.5^9*200 ≈ 0.39
Step-by-step explanation:
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..1
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34
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45
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56
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5i d
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6
Answer: The amount that Kristen would owe three months from now is $67.5
Step-by-step explanation:
The formula for determining simple interest is expressed as
I = PRT/100
Where
I represents interest paid on the loan.
P represents the principal or the current balance.
R represents interest rate
T represents the duration for which the account is overdue in years.
From the information given,
P = 1500
R = 18%
T = 3 months = 3/12 = 0.25 year
I = (1500 × 18 × 0.25)/100 = $67.5