November savings = 45
Step-by-step explanation:
Amount saved in June = 20
Amount saved in July = 25
Amount saved in August = 30
From the above, there is an increament of 5 as the month increases:
30-25 = 25-20 = 5
September = August savings + increament
September saving = 30 + 5 = 35
October = September savings + increament
October = 35 + 5 = 40
November = October savings + increament
November savings = 40 + 5
November savings = 45