Multiplying two digit numbers whose ten's place is the same number, and one's place add up to 10. Procedure: 1)Multiply the last digits and write the answer. 2)Multiply the first digit by one number higher. Write that answer in front. Example: 33 x 37. Multiply 3 x 7 = _____21. Then multiply 3 times 4 = 12. Answer 1221.