Q: I have a friend who is about to turn 65. He says he is not going to sign up for Medicare Part B until he turns 66. That's when he plans to apply for his Social Security and for his Medicare. But I told him he will pay a 10 percent penalty if he waits until age 66 to apply for Medicare Part B. Am I right?

A: Yes you are -- in most circumstances. But as with almost every government rule, there are exceptions.

There are two basic parts to Medicare. Part A provides hospital coverage and Part B covers almost all other medical expenses. Part A is free. Part B comes with a monthly premium -- currently $96.40. That amount is usually deducted from a Medicare beneficiary's Social Security check. But if he or she isn't getting Social Security benefits, the person is sent a bill every three months by Medicare officials.

As an inducement to encourage people to apply for Medicare at the normal eligibility age of 65, the law stipulates that a 10 percent penalty will be tacked on to the monthly premium of anyone who doesn't take Medicare Part B at 65. And that's 10 percent for each year they delay applying for Part B.

But here's the exception. The law says if you are still working at 65 and are covered by your employer's health insurance plan, or if your spouse is still working and you are covered by his or her employer's health insurance plan, then you DO NOT have to take Medicare Part B at age 65. You don't need to apply for Part B until you stop working and lose your employer's regular health coverage, or you lose your spouse's employer's health coverage.

Further, the law states that when you finally do apply for Part B, you will pay the regular monthly premium, with no penalties.

So, unless one of those exceptions applies to your friend, then you were correct to warn him that he will pay the penalty if he doesn't apply for Medicare Part B now.

Q: I just learned that my Medicare Part B premium for 2009 will be almost $200 per month instead of the normal $96 per month. A letter I got from Social Security said this is because my 2007 income was $150,000. I normally don't make anywhere near that kind of money. But in 2007, I sold some property that netted me that extra cash. Is there anything I can do about this?

A: Yes. You should contact the Social Security Administration and let them know you're not as rich as you appeared to be a couple years ago. If you show them proof of your normal yearly income, and assuming it's less than $82,000, they should be able to lower your premium to the normal $96.40 per month rate.

This is all part of a relatively recent change in the rules. For decades, the Medicare Part B monthly premium was the same for everyone. But Congress decided a few years back that wealthier people should pay higher rates.

Under the new rules, if you are single and your income is $82,000 or less, or if you are married and your income is $164,000 or less, you pay the regular monthly premium of $96.40.

But as your income rises, so does the Part B premium. It goes up in gradual increments topping off at $238 per month for individuals with a yearly income over $205,000 or married couples whose annual income is $410,000 or more.