Question

A woman invests $3000 in government bonds for 5 years at 7% simple interest.

a)Calculate the total interest she receives for 5 years.
b) Calculate the sum that must be invested in bonds to obtain a total interest of $3500 in 5 years.




help with b ??​

Answer 1

7000 dollar, I guess.

Explanation:

As we know the equation of simple interest is : I=Pnr

where I-interest

P-principal or in this case the sum

n- number of years

r- rate perchantage

as it asks for the sum, it should be:

P= I/nr

=3500 / 0.007 x 5 ( 7%= 0.007)

= 10000

as she already invested 3000, so remains = (10000-3000)

= 7000 dollar