Henry Sticker – The best way to Calculate Shortly: Full Course in Velocity Arithmetic
1955 | ISBN: 1607964201, 048620295X | English | 185 pages | PDF | 5.9 MB
Many helpful procedures defined and taught: two-column addition, left-to-right subtraction, direct multiplication by numbers larger than 12, psychological division of huge numbers, extra. Additionally quite a few useful brief cuts. Greater than eight,000 issues, with options.