Mathematics
General chapter practice
This Class 9 Mathematics topic provides focused practice for reviewing common chapter questions and strengthening problem-solving skills. Students work through familiar question types, learn to identify the relevant mathematical concept, choose an appropriate method, and present solutions in clear, logical steps. The practice also supports checking calculations, understanding errors, and revising key ideas from different chapters. It is useful for building confidence before classroom assessments, homework, and independent revision.
Topic overviewटॉपिक का परिचय
Concept revisionअवधारणाओं का पुनरावर्तन
If A = {2, 4, 6, 8}, in which form is A written?
A set is written in roster form when its individual elements are listed explicitly inside braces and separated by commas. In A = {2, 4, 6, 8}, every element is directly displayed, so this is roster form.
What is the roster form of B = {x : x is an odd natural number and x < 10}?
The set-builder condition requires x to be both a natural number and odd, with x less than 10. The odd natural numbers below 10 are 1, 3, 5, 7, and 9, so the roster form is B = {1, 3, 5, 7, 9}.
Which option correctly describes C = {a, e, i, o, u}?
A set is described by the common property shared by all its distinct elements. The symbols a, e, i, o, and u are the standard vowels of the English alphabet, so option A gives the exact description.