Which retail strategy did Texas Instruments use to establish dominance in the educational calculator market?

Texas Instruments calculators have been a staple in mathematics education for decades, with their iconic graphing calculators found in classrooms worldwide. The Ti-84 series in particular has dominated the educational calculator market since its introduction. But how much do you know about the retail strategy that made these devices so ubiquitous in mathematics education?

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Establishing contracts with textbook publishers to feature Ti calculators in examples and problems
Offering significantly lower prices than competitors during the back-to-school season
Creating a subscription model where schools receive free calculator updates annually
Implementing a buy-one-get-one program for mathematics departments at universities