John's father throws John a birthday party that costs $350. He pays $150 for the DJ, $50 for the cake and $3 per party guest for food. How many guest were at the party?

50

Step-by-step explanation:

The DJ and the cake costs are not affected by the number of guests. Only the cost of food is affected by the number of guests.

So the cost of food = $(350-150-50) = $150

Food for each guest costs $3 and in total cost $150.

Therefore there are 150/3 = 50 guests.

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Step-by-step explanation:

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