Question

So a certain someone deposit money but the interest rate dropped from
$3 \frac{3}{4} \: per \: annum \: to \: 3 \frac{1}{2} \: per \: annum$
aND the interest rate has made his annum decrease by $50
Find the sum of money this person deposited​

Answer 1

Answer:

$20000

Step-by-step explanation:

In 1st case,

Principal=?

Rate=15/4 per annum

Time= 1 year

Interest=?

I=PTR/100

I=(P*1*15/4)/100

I=15P/400

In 2nd case,

Principal=?

Rate=7/2 per annum

Time= 1 year

Interest=15P/400-50

Now,

I=PTR/100

15P/400-50=(P*1*7/2)/100

(15P-20000)/4=7P/2

(15P-20000)/2=7P

(15P-20000)=14P

15P-14P=20000

Therefore, The sum of money deposited was $20000.