Question

David earns 4% for the money he has in savings. Let a represent how much he has in his account. Write two expressions that can be used to calculate the amount of money in his account after one month

Answer 1

Answer:

I = a/300

A = (300I + a)/300

Step-by-step explanation:

David earns 4% for the money he has in savings. Let the amount that he has initially be a. This means that his principal is a. So

P = a

The rate at which he is earning interest on the principal is 4%. Therefore,

R = 4℅

We want to calculate the amount of money in his account after one month. This means that time,

t = 1/12 (12months make a year)

The amount of money in his account after one month will be the interest earned in one month + the initial amount in the account.

To determine the interest, we will apply the simple interest formula,

I = PRT/100

Where I = interest

P = principal

T = time

The first equation will be

I = (a × 4 × 1)/12 × 100

I = 4a/1200 = a/300

The second equation will be

Amount in the account after one month,A

A = I + a/300

A = (300I + a)/300