Add three or more numbers with different numbers of digits, with and without the use of digital technologies, eg 42 000 + 5123 + 246

1. Add these 3 numbers: 9+10+4
2. Add three numbers: 2 + 13 + 9
3. Add three numbers: 15 + 7 + 8
4. Add three numbers: 17 + 7 + 12
5. Add these 3 numbers: 80 + 70 + 40
6. Add these 3 numbers: 90 + 60 + 30
7. Add these 3 numbers: 40 + 70 + 20
8. Add these 3 numbers: 30 + 20 + 90
9. Add these 3 numbers: 70 + 90 + 10
10. Weigh Ho, Me Hearties! - adding masses in g
11. Weigh Ho, Me Hearties! Adding masses in kg