_____________________ | _________________ | | | | |
| | RETROFIT = £££ | |
| |_________________| | | ___ ___ ___ ___ | | | 7 | 8 | 9 | | + | | | |___|___|___| |___| | | | 4 | 5 | 6 | | - | | | |___|___|___| |___| | | | 1 | 2 | 3 | | x | | | |___|___|___| |___| | | | . | 0 | = | | ÷ | | | |___|___|___| |___| | |_____________________|