one continuation would be:
20, 40, 30, 60, 40, 80, 50
20 TIMES 2 = 40 AND 40+-70=-30
These may help you answer your questions: 1, 2, 4, 5, 8, 10, 20 and 40.
20 30 40
20, 40, 50
20 30 40 56
40 (+20, -10, +30 ,-20)
75/100, 15/20, 30/40
They are 24, 30 and 36
The sum of 40, 30, and 20 is 90. You can calculate this by adding the numbers together: 40 + 30 + 20 = 90.
If half of the number is 20, then the number must be 2 * 20 = 40. Therefore three quarters of the number would be 3 * (40/4) = 30.
50 + 40 + 40 + 40 + 30 + 30 + 20 + 10 = 260
4/20 21/30 28/40