UGC NET Questions (Paper – 1)

Statements A, B and C correctly describe mixture setups, the alligation shortcut and the fact that equal quantities lead to an average percentage. Statement E is true because both algebraic and alligation approaches are valid for such problems. Statement D is false since in an alligation diagram the differences from the mean are written on the opposite side to the corresponding values, forming the cross pattern. Therefore, A, B, C and E only are correct.

Option A:
Option A is incomplete because it omits E and hence does not reflect the flexibility of solving mixture problems either by equations or by alligation.

Option B:
Option B is correct as it gathers all the true statements and excludes D, which misdescribes the alligation diagram placement rule.

Option C:
Option C is wrong because it includes D (false), even though it contains some true statements.

Option D:
Option D is wrong because it includes D (false) and omits A, losing the general description of mixture problems.

Statements A, B, C and E are correct as they capture the essence of mixture problems: combining components, summing component quantities, using the rule of alligation as a shortcut and representing scenarios algebraically or graphically. Statement D is false because mixture questions are naturally modelled by weighted averages where proportions act as weights. Thus, the combination A, B, C and E only is correct.

Option A:
Option A is incomplete as it leaves out E, not mentioning that visual or diagrammatic approaches are often used to make mixture relationships clearer in exams. Without E, the modelling variety is understated.

Option B:
Option B is also incomplete because it omits A and thereby fails to state directly that mixtures can involve various types of components like solutions or grains, which is basic contextual information.

Option C:
Option C is correct because it collects all the true statements about mixture structures, alligation shortcuts and representation methods, while excluding D, which incorrectly denies the connection with weighted averages. This matches the treatment in UGC NET aptitude.

Option D:
Option D is wrong as it includes D, which wrongly claims that weighted averages cannot be used for mixtures, and omits B, which accurately describes how component quantities combine. The presence of D invalidates the set.

Statement A correctly describes the overall concentration as a weighted average of component concentrations. Statement B is a special case for equal quantities, where the weights are equal and the average is arithmetic. Statement C states the classical alligation rule connecting mixing ratio to the differences from the mean. Statement D is false because adding pure water does not change the solute amount, and E is false since diluting with water lowers concentration but does not decrease the amount of solute. Hence A, B and C only are correct, which corresponds to option A.

Option A:
Option A is correct because it includes the general weighted-average idea, its equal-quantity special case and the alligation rule, while excluding D and E, which misunderstand how solute amount changes under dilution.

Option B:
Option B is incorrect since it includes D, which wrongly asserts that adding pure water increases solute amount, mixing an error with accurate statements.

Option C:
Option C is wrong because it includes E (false: adding water alone does not reduce solute amount) and omits B (true equal-quantity averaging), so it does not match the true set.

Option D:
Option D is incorrect as it contains D (false) and omits A (the key weighted-average principle), making it both incorrect and incomplete.