The total planned cost for the party was 100*50 = $<<100*50=5000>>5000

The total expenses for the party are 5000-500 = $<<5000-500=4500>>4500

# Answer

4500
<|im_start|>system
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<|im_start|>user
Hally and her friends organized a high school reunion. To cover the cost of a late-night party that they planned for at the reunion, each attendee had to pay $100. After the party, Hally and her friends realized that the total expenses were $500 less than the total contributions. If there were 50 people at the party, how much money was used to pay for the party expenses?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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user
4500
Hally and her friends organized a high school reunion. To cover the cost of a late-night party that they planned for at the reunion, each attendee had to pay $100. After the party, Hally and her friends realized that the total expenses were $500 less than the total contributions. If there were 50 people at the party, how much money was used to pay for the party expenses?
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