## Tuesday, July 5, 2011

### Math Secrets in Sports: Tennis

Just when kids think they are getting the hang of math, (one, two, three - the higher you go the more value you have) they have to leave the comfort of the classroom and march out into the harsh sunlight on the playing field. There, in sometimes traumatic circumstances, they discover that the math they learned in the classroom is not enough to deal with sports!

This week in the Excel Math Blog we reveal the shocking inside mathematical secrets of  sports! Today we expose Tennis (because Wimbledon is just over) and tomorrow we will investigate Bowling (because so many millions of people participate). In each of these sports you have to learn new math or relearn your old math.

In Tennis you do more than count runs or hits or baskets or goals. You count up using new names for numbers, then count back, adjust your actions to suit the win by at least 2 points contingency rules, and so on.

I'll just give a brief overview of the math and terms used in Tennis:

TENNIS
TOURNAMENT - a competition where lots of tennis players compete to find the overall winner
MATCH - a player needs to win 2 out of 3 (or 3 out of 5) sets to win a match
SET - a player needs to win 6 games (and at least 2 more games than the opponent) to win a set
GAME - a player needs 4 points (and at least 2 more points than the opponent) to win a game
POINTS - the points are called:
• Love = 0
• First point = 15
• Second point = 30
• Third point = 40
• If both have 40 it's called deuce
• there's another term called advantage

A tennis court is shown below. It can be surfaced with clay, grass, wood or asphalt or other hard materials. A hard surface court will cost about \$25-30,000 to build.

A tennis court is 27 feet (singles) or 36 feet (doubles) wide and 78 feet long. The net is 3 feet 6 inches high at the ends, and can droop to 3 feet in the middle. Poles for the net are set 3 feet outside the doubles lines, so the net is 42 feet long [36 + 3 + 3 = 42] .

The court should be level with just enough slope for water to run off (a maximum of 1 inch in 10 feet of distance).

To avoid the players running into fences or stands, the court needs extra space around it - about 12 feet on each side and 21 feet at each end. To keep from losing tennis balls, and for safety, courts are usually surrounded by 10-foot chain-link fences.

You can buy a fence "kit" with all you need to enclose a pair of courts, for about \$12,000. That's 120 feet long, 120 feet wide, and 10 feet high with 2 gates. Wind screens for the fence cost an additional \$1000 or so.