Last updated at Jan. 17, 2020 by Teachoo
Transcript
Ex 3.2, 20 The bookshop of a particular school has 10 dozen chemistry books, 8 dozen physics books, 10 dozen economics books. Their selling prices are Rs 80, Rs 60 and Rs 40 each respectively. Find the total amount the bookshop will receive from selling all the books using matrix algebra. Number of chemistry books = 10 dozen = 10 × 12 = 120 Number of physics books = 8 dozen = 8 × 12 = 96 Number of economics books = 10 dozen = 10 × 12 = 120 Let matrix A denote the number of books per subject. A = [ 120 96 120 ] Let Matrix B denote the selling price of books per subject B = [█(80@60@40)] Now, Total amount the shopkeeper receives = Number of books × Selling price = AB = 〖"[ 120 96 120 ]" 〗_(1 × 3) [■8(80@60@40)]_(3 × 1) = 〖["120 × 80 + 96 × 60 + 120 × 40" ]〗_(1 × 1) = "120 × 80 + 96 × 60 + 120 × 40" = 9600 + 5760 + 4800 Chemistry = 20160 Hence, total amount received by shopkeeper is Rs. 20,160
Chapter 3 Class 12 Matrices
Ex 3.1, 9 Important
Example 18 Important
Example 19
Ex 3.2, 7 Important
Ex 3.2, 12 Important
Ex 3.2, 16 Important
Ex 3.2, 17 Important
Ex 3.2, 20 Important You are here
Example 22 Important
Ex 3.3, 4
Ex 3.3, 10 Important
Ex 3.3, 12 Important
Ex 3.4, 15 Important Deleted for CBSE Board 2022 Exams
Ex 3.4, 17 Important Deleted for CBSE Board 2022 Exams
Example 28
Misc. 3 Important
Misc. 9 Important
Misc. 11 Important
Misc. 13 Important
Chapter 3 Class 12 Matrices
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