Question

suppose aaron earned 15.75 in interest for account A and 28.00 in interest for account B after 21 months if the simple interest rate is 3.0% for account A and 4.0% for account B wich account has the greater principle explain

Answer 1

Answer:

Principle for account B is greater.

Step-by-step explanation:

First of all, let us have a look at the formula for Simple Interest:

$SI =\dfrac{PRT}{100}$

Where $P$ is the principle amount

$R$ is the Rate of interest per annum

$T$ is the time in years.

Time = 21 months = $\frac{21}{12}\ yrs$

$R_1 = 3\% \\R_2=4\%$

Let the Principles be $P_1, P_2$.

Using the formula for Simple Interest, we get:

$SI_1=\dfrac{P_1\times 3\times 21}{100\times 12}\\\Rightarrow 15.75=\dfrac{P_1\times 3\times 21}{100\times 12}\\\Rightarrow P_1 = 300$

$SI_2=\dfrac{P_2\times 4\times 21}{100\times 12}\\\Rightarrow 28=\dfrac{P_2\times 3\times 21}{100\times 12}\\\Rightarrow P_2 = 533.33$

Therefore, principle for account B is greater.