Math Through Sports
Solving for x in a stat line
7 min · Turn "what would it take?" into an equation and solve it.
- Basic algebra
- Percentages
The stat
Turn "what would it take?" into an equation and solve it.
Learn the number
Algebra starts when the unknown is the thing you want. Write the rule, put a letter where the unknown goes, then keep both sides balanced.
Completion percentage is completions ÷ attempts. If you want to know how many more completions are needed to reach a target rate, that rule becomes an equation.
Whatever you do to one side, do to the other. That is the entire method.
Read the stat
A quarterback is 18 of 24. If he completes the next x passes in a row, when does he reach 80%?
- After x more completions he is (18 + x) of (24 + x).
- Set that equal to 0.80: (18 + x) / (24 + x) = 0.80.
- Multiply both sides by (24 + x): 18 + x = 0.8 × (24 + x) = 19.2 + 0.8x.
- Subtract 0.8x from both sides: 0.2x + 18 = 19.2.
- Subtract 18: 0.2x = 1.2, so x = 1.2 ÷ 0.2 = 6.
Six more completions in a row: he would be 24 of 30, and 24 ÷ 30 = 0.80.
Your turn
A shooter is 6 of 10. How many made shots in a row does she need to reach 70%?
Explain what it means
The equation shows how much harder a rate is to move once the denominator is large. Six straight completions changes a 24-attempt season a lot and a 400-attempt season almost not at all.
Make a prediction
Take a player mid-season and work out how many consecutive successes they need to reach the next round number. Predict whether they get there this month.
Review what happened
Check the real line later. If the rate barely moved despite a good run, the denominator was the reason — not effort.
Check your understanding
0 of 3 correct
Every question has to be right for this lesson to count as complete. Miss one and you can try it again.