To find out what percentage of the total budget was spent on equipment, you can use the formula:
\[ \text{Percentage} = \left( \frac{\text{Amount spent}}{\text{Total budget}} \right) \times 100 \]
In this case, the amount spent on equipment is $180 and the total budget is $1000.
Plugging in the numbers:
\[ \text{Percentage} = \left( \frac{180}{1000} \right) \times 100 \]
Now, calculate the fraction:
\[ \frac{180}{1000} = 0.18 \]
Then multiply by 100 to get the percentage:
\[ 0.18 \times 100 = 18 \]
Thus, the friends spent 18% of their total budget on equipment.