Compound interest in exercise,$3000 is invested in an account at interest rate r, compounded continuously. find the time required for the amount to (a) double and (b) triple.
r = 0.085

(a) 8.15

(b) 12.92

Step-by-step explanation:

Given: P = $3000, r = 0.085

Where

A is the Amount

P is the Principal

r is the rate

t is the time

(a) For the amount to double, A = 2 × P

               A = 2 × $3000

               A = $6000

Take of both sides

But

            ∴

               t = 8.15

(b) For the amount to double, A = 3 × P

               A = 3 × $3000

               A = $9000

Take of both sides

But

            ∴

               t = 12.92