Question

find the cost of 30 notebooks at the rate 20 per dozen
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Answer 1

Answer:

50

Step-by-step explanation:

1 dozen=12

cost of books per dozen=20

cost of 30 books=(20/12)×30

=50

therefore cost of 30 books is rs.50

Answer 2

Answer:

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cost of 12 notebooks is = $20

:.(cost of 1 dozen notebook)

cost of 1 notebook= $20/12

cost of 30 notebook

= $ 20/12×30

= $ 50

hence the cost of 30 notebook is $50