Respuesta :

Answer:

number next in the sequence = 20

Step-by-step explanation:

5, 20, 10, 30, 15, 40, (20) ---> (40 - 20 = 20)

+15 -10 +20 -15 +25 (-20) ---> (25  - 45 = -20)

  -25 +30 -35 +40 (-45)