The percentage, P, of U.S. voters who used punch cards or lever machines in national elections can be modeled by the formula P=−2.5x+63.1 where x is the number of years after 1994. In which years will fewer than 38.1% of U.S, voters use punch cards or lever machines?

The percentage, P, of U.S. voters who used punch cards or lever machines in national elections can be modeled by the formula P=−2.5x+63.1 where x is the number of years after 1994. In which years will fewer than 38.1% of U.S, voters use punch cards or lever machines?

Question
Equations and inequalities
asked 2021-02-16
The percentage, P, of U.S. voters who used punch cards or lever machines in national elections can be modeled by the formula P=−2.5x+63.1 where x is the number of years after 1994. In which years will fewer than 38.1% of U.S, voters use punch cards or lever machines?

Answers (1)

2021-02-17
Using the given formula, we substitute P=38.1 (for 38.1%) and solve for x:
38.1=-2.5x+63.1
-25=-2.5x
-25/-2.5=x
x=10
which corresponds to the year 1994+10=2004. Hence, the years where fewer than 38.1% of U.S. voters use punc cards or lever machines is 2004 adn beyond.
0

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