The formula for simple interest is <em>I</em> = <em>prt</em>, where <em>I</em> is the amount of interest, <em>p</em> is the principal borrowed, <em>r</em> is the interest rate written as a decimal number, and <em>t</em> is the amount of time in years. First we find the amount of interest. He borrowed $35000 but paid back $46375. That means he paid 46375-35000 = $11375 in interest. We can now substitute our information into our interest formula:
11375=35000(<em>r</em>)(5)
11375=35000(5)(<em>r</em>) ----- remember that multiplication is commutative
11375=175000<em>r</em>
Divide both sides by 175000 to cancel it:
11375/175000 = 175000<em>r</em>/175000
0.065 = <em>r</em>
To convert this to a percentage, we multiply by 100:
0.065(100) = 6.5%
The 2 triangles are congruent
Step-by-step explanation:
So the general formula for compound interest is
where t is typically time in years, and n is how many times it's compounded per year. But in this case it's only compounded 1 time per year so the equation is just
. in this case P is the principal amount, r is the interest, and A is the final amount. So the 5% interest rate becomes 0.05 by dividing by 100 to convert it into decimal form and the principle amount of 11,000. This gives you the formula
. This is the answer to the first question where t is the time in years. When it says "Find interest earned" I'm a bit confused, is it giving you x amount of years where you have to calculate the interest earned or does it want a general equation? Because the general equation would be the final amount - the principle amount which calculates the difference. So the equation for interest earned would be
. To calculate the amount of money after 5 years you simply plug in 5 as t. this gives you the equation 