P = ?, r=4%, t=3 months, I=$20

P = $ 2,000.00

Equation:

P = I / rt

Calculation:

First, converting R percent to r a decimal

r = R/100 = 4%/100 = 0.04 per year,

putting time into years for simplicity,

3 months : 12 months/year = 0.25 years,

then, solving our equation

P = 20 / (0.04 * 0.25) = 2000

P = $ 2,000.00

The principal required to

accumulate interest of $ 20.00

on a rate of 4% per year for 0.25 years (3 months) is $ 2,000.00.