To determine the total number of parking spaces in the garage, we need to add the 551 parked cars and all empty spaces on each level.

Here’s the calculation:

$\text{Total spaces} = \text{Cars parked} + \text{Empty spaces (1st level)} + \text{Empty spaces (2nd level)} + \text{Empty spaces (3rd level)}$

Substituting the values:

$\text{Total spaces} = 551 + 128 + 294 + 302$

Adding these together:

$\text{Total spaces} = 551 + 128 + 294 + 302 = 1275$

Answer: There are 1,275 spaces in the parking garage.

Would you like further details, or do you have any questions?

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Here are some related questions to consider:

1. If 10% of spaces become unavailable, how many would still be available?
2. How many more cars can park if each level fills all its empty spaces?
3. What percentage of the parking garage spaces are currently occupied?
4. If each level has an equal number of parking spaces, how many would each level have?
5. How many spaces would remain empty if 100 more cars arrived?

Tip: Adding grouped numbers, like empty spaces on each level, first can simplify large calculations.