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The average of 20 numbers is 80. The ave...

The average of 20 numbers is 80. The average of first 10 numbers is 76.5 and that of next 7 numbers is 82. The 18th number is 3 more than the 19th number but 3 less than the 20th number. What is the average of 18th and 19th numbers?

A

`88.5`

B

`85.5`

C

86

D

85

Text Solution

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The correct Answer is:
C
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