60 years, 720 months, 3120 weeks, 21,915 days

That's a long time. It's how long my mother-in-law and father-in-law have been married, as of today. It's their anniversary. Here's a picture of them about 40 years ago.

Anniversaries are fun times to remember "the old days"which for some of us were a long time ago. And they are an occasion to use our elementary school math. Here's a recent picture of Phil and Joan.

If you can imagine it, the oldest persons alive have lived nearly twice as long as my in-laws have been married! This is Eugenie Blanchard, who has been alive for 114 years, 128 days!

Let's try some math questions:

Q1. How many days has Eugenie lived?

A1. days per year (114 x 365) + leap days (114/4) + 128 days =  41,610 + 28 + 128 = 41,766

Q2. What is the percentage of days that Eugenie has lived that Phil and Joan have been married?

A2. 21915 ÷ 41,766 or simplified, they have been married for 52% of her life.

Q3. My wife and I have been married for 12,710 days. How many years had Phil and Joan been married when we got married?

A3. You can do the math yourself. The answer is 25.17 years!