Question 1197959
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If 28 students pay $30 each, then that's 28*30 = 840 dollars total.


Now consider only 21 students attend. If the total cost stays at $840, then each student now has to pay 840/21 = 40 dollars.


The cost per person has increased by $10 since 40-30 = 10.


Answer: $40 per person
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