Answer:
18 sq. unit
you can draw it on no. line
actually it's rectangle with l=3 and b=6
(x^2-1)(x^2+7) should be your answer
The probability that he first chooses an advanced book and then chooses a beginner book is 6/121.
<h3>Probability</h3>
Given:
Beginner book=2
Intermediate book=6
Instructional piano books=11
Advanced books=3
Hence:
Probability=(2×3)÷(11×11)
Probability=6/121
Therefore the probability that he first chooses an advanced book and then chooses a beginner book is 6/121.
Learn more about probability here: brainly.com/question/24756209
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