# 1615 Should Today Be Root Ten Day?

### Today’s Puzzle:

In a recent post, I compared π or (3.14…) with √10 or (3.16…). Steve Morris lives in England where today’s date is written 16-3, not 3-16. He jokingly commented, “So I guess Tuesday (16 March) should be Root Ten Day!” Seriously, day-month-year makes more sense as a writing convention than month-day-year.

Should today be Root Ten Day?
14 March has long been embraced as pi day in the United States, but should 16 March also be a quasi-holiday where kids eat roots like ten French fries or ten carrot sticks?

I remember one of my college professors telling his class that
√2 is about 1.4, and Valentines day is February 14,
√3 is about 1.7, and Saint Patrick’s day is March 17.

√1 is 1, and New Year’s Day is January 1, and
√10 is about 3.1, and Halloween is October 31. (I realize there is a rounding issue with that one.)

Oops. That could be said about all the fake holidays I’ve listed above.

And here’s a more serious thought:

Well, however you want to remember what √10 is or not, I decided to make today’s puzzle look like a square root sign for the fun of it. Write the numbers from 1 to 12 in both the first column and the top row so that the puzzle functions like a multiplication table.

### Factors of 1615:

• 1615 is a composite number.
• Prime factorization: 1615 = 5 × 17 × 19.
• 1615 has no exponents greater than 1 in its prime factorization, so √1615 cannot be simplified.
• The exponents in the prime factorization are 1, 1, and 1. Adding one to each exponent and multiplying we get (1 + 1)(1 + 1)(1 + 1) = 2 × 2 × 2 = 8. Therefore 1615 has exactly 8 factors.
• The factors of 1615 are outlined with their factor pair partners in the graphic below.

### More about the Number 1615:

1615 is the hypotenuse of FOUR Pythagorean triples:
247-1596-1615, which is 19 times (13-84-85),
684-1463-1615, which is 19 times (36-77-85),
760-1425-1615, which is (8-15-17) times 95, and
969-1292-1615, which is (3-4-5) times 323.