| Number | Name | Date | Kind |
|---|---|---|---|
| 1151279 | Lewis | Aug 1915 | |
| 1428206 | Benton | Sep 1922 | |
| 1649578 | Deming | Nov 1927 | |
| 2494469 | Booth | Jan 1950 | |
| 2611193 | Davis | Sep 1952 | |
| 2835988 | Hilkene | May 1958 | |
| 3094792 | Morgan | Jun 1963 | |
| 3171217 | Birdsall | Mar 1965 | |
| 3204343 | Pollock | Sep 1965 | |
| 3414986 | Stassen | Dec 1968 | |
| 3636230 | Tacey | Jan 1972 | |
| 4914019 | Chu | Apr 1990 | |
| 5137452 | Pollock | Aug 1992 | |
| 5176577 | Pollock | Jan 1993 | |
| 5238407 | Pollock | Aug 1993 | |
| 5238408 | Pollock | Aug 1993 | |
| 5297965 | Manancero | Mar 1994 |
| Number | Date | Country |
|---|---|---|
| 8502207 | May 1985 | BRX |
| 2410319 | Nov 1977 | FRX |
| 1954660 | Feb 1967 | DEX |
| 7730826 | Jan 1978 | DEX |
| 9003865.7 | Feb 1992 | DEX |
| 1372163 | Oct 1974 | GBX |
| Entry |
|---|
| "Rainbow Fraction Tiles", manufactured by Learning Resources, Inc. of Lincolnshire, Illinois (1992). |
| "Fraction Stax .RTM.", manufactured by Ideal School Supply Company, Oak Lawn, Illinois (1992). |
| "Fraction Bars", manufactured by Scott Resources, Fort Collins, Colorado 1991. |