An account earns 5.5% interest and after two years the balance is $3330. Find the principle that was invested.

$3000.

Step-by-step explanation:

Simple interest formula,

I = (P*R*T)/100

Where,

P = original investment l,

R = rate of the interest,

T = time of the rate accured,

I = interest.

Balance = interest, I + original investment, P.

3330 = (P*5.5*2)/100 + P

Making P the subject of formula,

3330 = 0.11P + P

1.11P = 3330

Therefore,

P = $3000

$3000 was the principal investment.