# What was the average for the last 20 sittings?

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At the state fair eating contest the winner ate an average of 15 burgers at the first 20 sittings.
After a further 20 sittings the average increased to 20 burgers.
What was the average for the last 20 sittings?

posted Oct 1, 2018

15 * 20 + x * 20 = 20*40
x = 25
average for the second half = 25.

answer Oct 1, 2018

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