One idea at a time · explore as you learn1 / 11
When does benefit per baht lead to a corner or a kink?
If two pen brands are perfect substitutes, why buy both?
EC311 / GRAPHTry changing a value
1 Predict → 2 Try → 3 Explain → 4 Challenge
Why do some preferences have no tangency?
Illustrative model numbers, not Thailand or current economic data.