Abacus Tutorial: 2 The "exchange method" - calculating up to 5
Abacus Tutorial: 4 The exchange method -calculating up to 10 and more
Cranmer Abacus - 2 (Simple Addition with 4/5 Exchanges)
(5.3) Abacus: Addition, Practicing the 49-50 Exchange, 2 digits
Lesson 2 - How to use the Abacus aka Soroban? Simple Addition & Subtraction Questions
(8.5) Abacus: Practicing Subtraction, 4/5 Two Digit Exchange
(3.2) Abacus: Addition, Practicing the 4-5 Exchange
(8.6) Abacus: Practicing Subtraction, 4/5 Three Digit Exchange
(10.3) Abacus: Demonstration of Subtraction, 49/50 Exchange
(5.2) Abacus: Addition, Practicing the 49-50 Exchange
(3.3) Abacus: Addition, Practicing the 4-5 Exchange, 2 Digits
(4.2) Abacus: Addition, Practicing the 9-10 Exchange
(11.1) Abacus: Intro to 99/100 Exchange for Subtraction
(10.5) Abacus: Practicing Subtraction, 49/50 Exchange
(10.2) Abacus: Subtraction - 49/50 Exchange
(10.4) Abacus: Practicing Subtraction, 49/50 Exchange
(8.2) Abacus: Intro to 4/5 Exchange for Subtraction
(3.4) Abacus: Addition, Practicing the 4-5 Exchange, 3 Digits
(2.1) Abacus: Addition, No Exchange Demonstration
(5.4) Abacus: Addition, Practicing the 49-50 Exchange, 3 digits