Question
In 2018, an online course had 'r' subscribers.
Subscribers increased by 50% in 2019 and another 25% in 2020. However, in 2021 subscribers decreased by 40%. If the percentage of active users was 50% in 2018 and 60% in 2021, what is the percentage change in the number of active users?Solution
ATQ, Let the number of subscribers in 2018 be 4000. In 2019, subscribers = 1.50×4000=6000. In 2020, subscribers = 1.25×6000=7500. In 2021, subscribers decreased by 40% = 0.60×7500=4500. Active users in 2018 = 0.50×4000=2000. Active users in 2021 = 0.60×4500=2700. Percentage change in active users = {(2700−2000)/2000}×100% = 35%. Therefore, the number of active users increased by 35% from 2018 to 2021.
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