To calculate the simple interest for this example, you’d multiply the principal ($5,000) by the annual percentage rate (5 percent) by the number of years (five): $5,000 x 0.05 x 5 = $1,250 ...

Tax preparation companies define simple returns differently, but most free filing services are limited to basic Form 1040 returns. For example, TurboTax’s Free Edition is available to ...