Mathematical Puzzles — Mains Strategy

Mains Strategy

Written mathematical-puzzle questions here are reasoning practice, not a descriptive CSAT Mains component. A good response explains how the words become relationships, solves the smallest useful model and checks the answer in the original conditions. Keep the notation readable and attach units or state labels where they prevent ambiguity.

For a digit problem, derive the factor nine from place value rather than quoting it without explanation. For an age problem, show that both people gain the same twelve years. For a transfer problem, distinguish the two alternative experiments from a sequence of transfers. These steps teach why the equation is appropriate instead of presenting algebra as an unexplained shortcut.

The conclusion should identify the requested quantity precisely. A valid solution may contain several numbers: the child's present and future ages, both boxes' initial counts and their changed counts, or several valid remainder candidates. Reporting the wrong member of that set is still an error. Explain one plausible distractor by the condition or state it confuses, then give a direct substitution check.