Question

If the principal is $300 rate 3% time 4 years then what is the interest earned and the new balance

Answer 1

Answer:

a) Interest earned = $36

New Balance  = $336

b) Interest rate  = 0.05 or 5%

New Balance = $517.5

c) time t = 5

New Balance = $612.5

d) Principal Amount = $675

New Balance =  $783

Step-by-step explanation:

We are given:

a) Principal (P) = $300

Rate (r) = 3% or 0.03

Time (t)= 4 years

Interest earned = ?

The formula used is: $Simple \ Interest (I)= P\times r\times t$

Putting values and finding interest

$Simple \ Interest (I)= P\times r\times t\\Simple \ Interest (I)= 300\times 0.03\times 4\\Simple \ Interest (I)= 36$

So, Interest earned = $36

New Balance = Principal + Interest = 300+36 = $336

b) a) Principal (P) = $300

Rate (r) = ?

Time (t)= 3 years

Interest earned = 67.50

The formula used is: $Simple \ Interest (I)= P\times r\times t$

Putting values and finding rate

$Simple \ Interest (I)= P\times r\times t\\67.50= 450\times r\times 3\\67.50=1350\times r\\r=\frac{67.50}{1350}\\r=0.05 \ or \ 5\%$

So, Interest rate  = 0.05 or 5%

New Balance = Principal + Interest = 450+67.50 = $517.5

c) Principal (P) = $500

Rate (r) = 4.5% or 0.045

Time (t)= ?

Interest earned = $112.50

The formula used is: $Simple \ Interest (I)= P\times r\times t$

Putting values and finding time

$Simple \ Interest (I)= P\times r\times t\\112.50= 500\times 0.045\times t\\112.50=22.5 \times t\\t=\frac{112.50}{22.5}\\t=5$

So, time t = 5

New Balance = Principal + Interest = 500+112.50 = $612.5

d) Principal (P) = ?

Rate (r) = 8% or 0.08

Time (t)= 2 years

Interest earned = 108.00

The formula used is: $Simple \ Interest (I)= P\times r\times t$

Putting values and finding Principal

$Simple \ Interest (I)= P\times r\times t\\108=P\times 0.08 \times 2\\108=P\times 0.16\\P=\frac{108}{0.16}\\P=675$

So, Principal Amount = $675

New Balance = Principal + Interest = 675+108 = $783