Question

Micah deposits C dollars in a bank. The deposited amount earns an annual interest rate of r% and becomes D dollars in t years according to the formula Which formulas could be used to calculate t given C,D, and r

Answer 1

Answer:

$t = \frac{100}{r} [\frac{D}{C} - 1]$

Step-by-step explanation:

Assume that the deposited amount C dollars earn r% simple interest annually.

If after t years the deposited amount C dollars grows to D dollars, then we are asked to write a relation using the given terms to calculate t.

Now, using the formula of simple interest we can write

$D = C(1 + \frac{t\times r}{100})$

⇒ $1 + \frac{t \times r}{100} = \frac{D}{C}$

⇒ $\frac{t \times r}{100} = \frac{D}{C} - 1$

⇒ $t = \frac{100}{r} [\frac{D}{C} - 1]$

So, this is the expression for t. (Answer)

Answer 2

Answer:

t= 100/r [d/c-1]