teachers math answer book

Question: From 12 books, in how many ways can 5 be chosen i. to surely include a particular book ii. never to include a particular book iii. to have no restrictions at all? Answer: i. To include a particular book, one particular boo..

Question: For the post of 5 teachers, there are 23 applicants. 2 posts are reserved for S.C. candidates and there are 7 S.C. candidates among applicants. In how many ways can the selection be made? Answer: There are 23 applicants. Among this, 7 are S.C. candidates. W..

The given tally chart shows the numbers of parents who attended the parent-teachers meeting conducted in a school each month. Choose the appropriate label for the left side of the graph. => Number of drinks sold or Number of vegetables sold or Number of books or Number of parent..

Let the n t h term of series be an 3 + bn 2 + cn + d t n = an 3 + bn 2 + cn + d where a, b, c, d are constants. ..

Subtracting (ii) from (i), we get ..

i) 1.2 + 2.4 + 3.8 +.... to n terms The n t h term of (1,2,3,....n) is n. The n t h term of (2,4,8,...) is The n t h term of the given series is n2 n Subtracting (ii) from (i), we have ..

The determinant of coefficients ..

. . . . . . . . . . . . Adding vertically, ..

Subtracting (ii) from (i), we get ..

From (1) and (2), (A + B) + C = A + (B + C) \ The associative law is verifi..