№124 3)20,70,30,80,40, ...

Question

№124 3)20,70,30,80,40, ...

Answer 1

90
т.к.
+50-40+50-40...

Comments

а дальше как

Answer 2

20,70,30,80,40,90,50,100,60,110,70,120,80,130,90,140,100,150.