Let's denote the number of bicycles as \( b \) and the number of unicycles as \( u \).
From the information given:
- A bicycle has 1 seat and 2 wheels.
- A unicycle has 1 seat and 1 wheel.
We have the following equations based on the counts of seats and wheels:
-
The total number of seats is given by: \[ b + u = 18 \quad \text{(equation 1)} \]
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The total number of wheels is given by: \[ 2b + u = 28 \quad \text{(equation 2)} \]
Now, we can solve the system of equations.
First, let's solve equation 1 for \( u \): \[ u = 18 - b \]
Next, we can substitute \( u \) from this equation into equation 2: \[ 2b + (18 - b) = 28 \]
Now simplify: \[ 2b + 18 - b = 28 \] \[ b + 18 = 28 \] \[ b = 28 - 18 \] \[ b = 10 \]
Now we can find \( u \) using equation 1: \[ u = 18 - b = 18 - 10 = 8 \]
Thus, the owner has:
- 10 bicycles
- 8 unicycles
So, the fill-in-the-blanks would be: A bicycle has 1 seat and 2 wheels. A unicycle has 1 seat and 1 wheel. There are a total of 18 seats and 28 wheels.