Math Education Tool
Odds Classroom
A probability lesson disguised as a betting simulator. Students discover why even winning 50% of bets leads to bankruptcy.
The Challenge
"I'll give you $1,000 to bet with."
The odds are fair: both teams have an equal 50% chance of winning.
Can you make money?
What Students Think
- "If it's 50/50, I'll break even!"
- "I just need to pick winners"
- "I'll quit when I'm ahead"
- "Sports knowledge helps me win"
What Actually Happens
- Even at 50% wins, you lose money
- The "vig" guarantees house profit
- Math doesn't care about hot streaks
- Time is the house's best friend
What is the "Vig"?
The "vig" (short for vigorish, also called "juice") is how sportsbooks guarantee profit. It's hidden in the odds themselves.
Standard American Odds Example:
Team A
-110
Bet $110 to win $100
Team B
-110
Bet $110 to win $100
The Hidden Math:
- • If odds were "fair," you'd bet $100 to win $100 (even odds)
- • But at -110, you risk $110 to win only $100
- • On 1,000 coin flips, you'd win 500 × $100 = $50,000
- • But you'd lose 500 × $110 = $55,000
- • Net loss: $5,000 (even with perfect 50% luck!)
The Math Never Lies
Whether you're a student learning probability or someone considering sports betting, remember: the house edge is real, unavoidable, and guaranteed to take your money over time.