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please help with equation for interest
if a principle of 2000 at rate of 6% earns 300, how much will principle of 4000 earn at 8%?
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In this post, the problem is formulated INCORRECTLY.
The correct formulation is as follows:
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| If a principal of 2000 at simple annual interest rate of 6% |
| earns 300 in some time interval, how much will a principal |
| of 4000 earn at 8% simple annual interest rate |
| during the same time interval ? |
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Solution
Use the formula for simple interest
I = P*r*t, (1)
P is the principal, t is the time (in years), r is the annual simple interest rate,
I is the interest amount.
For the first scenario, we have
300 = 2000*0.06*t.
From this equation, find time t = = 2.5 years.
So, the time period is 2.5 years.
Apply the formula (1) AGAIN, this time for the second scenario
I = 4000*0.08*2.5 = 800.
ANSWER. The second interest amount is 800.
Solved and thoroughly explained.
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To see many other similar (and different) solved problems on simple interest accounts, look into the lesson
- Simple interest percentage problems
in this site.
Learn the subject from there.