NCERT Solutions for Class 9 Social Science Chapter 8: Building Blocks in Economics: The Problem of Choice – Free PDF Download

Chapter 8 of the new NCERT Class 9 Social Science textbook is Building Blocks in Economics: The Problem of Choice, part of the Economics section. It introduces the basic economic problem of scarcity and choice.

Last Updated: September 23, 2026

Scarcity and Choice

Q: What is the basic economic problem discussed in this chapter?
A: The problem of scarcity — human wants are unlimited, but the resources available to satisfy them are limited, forcing individuals and societies to make choices about how to use those resources.

Needs vs Wants

Q: What is the difference between a need and a want?
A: A need is something essential for survival, like food, water, and shelter; a want is something desired but not essential for survival, like a new gadget or a vacation.

Opportunity Cost

Q: What is opportunity cost?
A: Opportunity cost is the value of the next best alternative given up when a choice is made — for example, if you spend your pocket money on a book, the opportunity cost might be the movie ticket you could have bought instead.

Opportunity Cost Beyond Money

Q: Give an example of opportunity cost involving time rather than money.
A: Choosing to spend an evening studying means giving up the opportunity to spend that same evening watching a movie or meeting friends — the value of that foregone activity is the opportunity cost.

Frequently Asked Questions

Why does scarcity force people to make choices?
Because resources like money, time, and materials are limited, people cannot have everything they want, so they must choose which wants to satisfy and which to leave unmet.

Is opportunity cost only about money?
No, opportunity cost can apply to non-monetary resources too, such as time — for example, choosing to study means giving up the opportunity to spend that time on something else.

Written by Satish

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